Sony KD-65A1 (EU A1E equivalent), Apple TV 4K and HDMI-CEC woes

[PavelPr]

Hi!

I am experiencing a very strange situation with my configuration on which I hoped somebody could shed some light.

I own a Sony KD-65A1 TV connected via its HDMI 3 (ARC) port to a Sony STR-DH770 receiver. Formerly, I used to own a 4th generation Apple TV which was connected to the TV directly and worked great.

Last Friday I went out and bought an Apple TV 4K. Having connected it directly to the TV's HDMI port 2 (not via the receiver), it initially worked fine. However, something strange happens after both devices would enter standby for a period of roughly 30 minutes or longer: once turned back on, the TV would not be able to detect any signal from the Apple TV.

The TV would be able to tell that the Apple TV is connected to it; it would also be able to specify the resolution at which the video signal is ostensibly transmitted, it would also "flicker" briefly (in what appears to be an attempt to establish connection) but no picture would appear. Both the TV and the Apple TV are updated to their respective latest software releases (TV firmware version 6.2858 and tvOS 11.3).

While experimenting with this, I've made the following observations:

1. Once the problem occurs, the only way to regain connectivity under said configuration is to either power-cycle or restart (using the "Restart" option that's under the "About" menu) the TV itself. Power-cycling just the Apple TV bears no effect;

2. In some (not all) instances, the Apple TV has to be power-cycled too as it would become non-responsive to its own remote control, wouldn't "wake up", and the only way to then regain device responsiveness is to physically unplug and re-plug its power cord;

3. Changing the HDMI cable to a more expensive one had no effect;

4. Restoring both the TV and the Apple TV to their factory defaults had no effect;

5. Once the issue manifests, connecting the Apple TV (apart from instances where it wouldn't turn on) to another HDMI port (1 or 4) would work. Likewise, connecting another device to HDMI port 2 (to which the Apple TV is usually connected) works properly as well (not entirely correct, see update below). Moreover, disabling "Enhanced HDMI" mode on the TV results in regained connectivity, albeit without HDR or Dolby Vision support.

At this point, the only way to regain proper connectivity under the original configuration is to power-cycle or soft-restart the TV. To me, it appears as though something in the "marriage" of the Apple TV with a particular HDMI port breaks until the TV itself is power-cycled or restarted.

And then it finally dawned on me: in the Apple TV, I usually have the ability to turn on the TV with the Apple TV remote disabled ("Settings" -> "Remotes and Devices" -> "Turn On Your TV with Your Remote"). Once I re-enabled this setting, and ensured that the TV would be turned on and off via the Apple TV, the issue bizarrely disappeared. Once I turned that option back off, the issue started recurring.

Still, I am not interested in having the Apple TV control my devices in this manner and prefer to have that setting off. I have seen a variety of Apple TV 4K HDMI CEC-related issues documented on these forums, some of which were fairly similar to mine, with the exception being the fact that while other posters reported that restarting the Apple TV helps, nothing short of power-cycling the TV itself works for me. It seems as though some kind of state gets corrupted, otherwise I have no way of explaining this behavior.

Did anyone ever experience anything like this?

Thanks in advance!

UPDATE (April 28th): After digging a bit further, it appears as though this situation is somewhat more insidious than it would at first appear.

Pursuant to point 2 above, when the Apple TV 4K is connected to HDMI port 2 and this issue would appear after standby, HDMI port 2 would work with other devices, given that these devices don't utilize "Enhanced HDMI" mode. Connecting an HDR-enabled device (a PlayStation 4 Pro, for instance), however, to HDMI port 2 results in a frequent, intermittent loss of signal. The only way then to regain proper function is to power-cycle the TV.

I am almost confident that a hardware issue with the TV can be ruled out here, as had such been the case, functionality would not be restored upon performing a power-cycle or a soft-restart.

I have a strong sense of conviction that for some reason unbeknownst, some form of "state" is presumably being corrupted such that Enhanced HDMI is knocked out until the TV is restarted.

 

[Phil in ocala]

Hi!

I am experiencing a very strange situation with my configuration on which I hoped somebody could shed some light.

I own a Sony KD-65A1 TV connected via its HDMI 3 (ARC) port to a Sony STR-DH770 receiver. Formerly, I used to own a 4th generation Apple TV which was connected to the TV directly and worked great.

This Friday I went out and bought an Apple TV 4K. Having connected it directly to the TV's HDMI port 2, it initially worked fine. However, something strange would happen after both devices would enter standby for about 30 minutes or longer: once turned back on, the TV would not be able to detect any signal from the Apple TV. Both the TV and the Apple TV are updated to their respective latest software releases (TV firmware version 6.2858 and tvOS 11.3).

While experimenting with this, I've made the following observations:

1. Once the problem occurs, the only way to regain connectivity is to either power-cycle or restart (using the "Restart" option that's under the "About" menu) the TV itself. Power-cycling just the Apple TV bears no effect;

2. In some (not all) instances, the Apple TV has to be power-cycled too as it would become non-responsive to its own remote control, wouldn't "wake up", and the only way then to regain responsiveness is to physically unplug and re-plug its power cord;

3. Changing the HDMI cable to a more expensive one had no effect;

4. Once the issue manifests, connecting the Apple TV (apart from instances where it wouldn't turn on) to another HDMI port (1 or 4) would work. Likewise, connecting another device to HDMI port 2 (to which the Apple TV is usually connected) works properly as well. Moreover, disabling "Enhanced HDMI" mode on the TV results in regained connectivity, albeit without HDR or Dolby Vision support. It appears as though something in the "marriage" of the Apple TV with a particular HDMI port stops working until the TV itself is power-cycled or restarted.

5. Restoring both the TV and the Apple TV to their factory defaults had no effect;

And then it dawned on me: in the Apple TV, I usually have the ability to turn on the TV with the Apple TV remote disabled ("Settings" -> "Remotes and Devices" -> "Turn On Your TV with Your Remote"). Once I re-enabled this setting, and ensured that the TV would be turned on and off via the Apple TV, the issue bizarrely disappeared.

Still, I am not interested in having the Apple TV control my devices in this manner. I have seen a variety of Apple TV 4K HDMI CEC-related issues documented on these forums, some of which were fairly similar to mine, with the exception being the fact that while other posters reported that restarting the Apple TV helps, nothing short of power-cycling the TV itself works for me. It seems as though some kind of state gets corrupted, otherwise I have no way of explaining this behavior.

Did anyone ever experience anything like this?

Thanks in advance!

>>>>>>
If possible to a reset of the processor of the TV.....I have had to reset my Yamaha receiver multiple times with these kinds of issues et al.

 

[PavelPr]

How do you mean? I did a factory reset of the TV in order to troubleshoot these issues, but to no avail.

 

[Phil in ocala]

A spray can of a product called DeoxIT d5 has solved many problems for me...I was getting no signal from my hdmi to my yamaha...sprayed the connections and it worked....this is a great product I have used for years...U can buy it on ebay...worth every dime...

 

[PavelPr]

The connectors and the TV are brand new. This appears like a case of incompatibility.

 

[Phil in ocala]

The connectors and the TV are brand new. This appears like a case of incompatibility.

All of the cables we use are Chinese made....and many are just crap....there is not such thing as incompatibiity ...take my advice for the product or just put up with it.

 

[PavelPr]

The cables are brand-new, relatively expensive Audioquest ones.

Having worked in software engineering for a considerable number of years, I would respectfully disagree with the statement of "there is not such thing as incompatibility" (just search these forums for similar issues, you'll find plenty). You might also want to re-read my description of the issue.

 

[Phil in ocala]

I was talking about consumer products...if you have this kind of background then fixing this issue should be easy for you.

 

[PavelPr]

I have no access to the design details of either product. All I could do is pinpoint the issue as narrowly as I could – which boils down to some bug related to HDMI control, when such control is disabled (which is quite bizarre), and both devices are on standby for a considerable amount of time.

 

[priitv8]

I have no access to the design details of either product. All I could do is pinpoint the issue as narrowly as I could – which boils down to some bug related to HDMI control, when such control is disabled (which is quite bizarre), and both devices are on standby for a considerable amount of time.

While I have no good solution to your problem, I can attest that my Z9D and appleTV and Arris IPTV set-top box do not play well together on CEC either.
I run all my devices via STR-DN1080 AVR, only HDMI 3 (ARC) is connected at TV.
From CEC logs I can only see, that aTV is losing it's logical address and needs to start re-acquiring it (btw hot-plugging HDMI forces this to happen as well).
Disconnecting CEC from Arris (NB! physically disconnecting HDMI pin 13, not just disabling in software) has alleviated the problem for me. At least now aTV is always responsive to CEC commands. I have not had the screen blanking issue after wakeup.
I believe in general, the codebase for A1 and Z9D is the same. I have the EU version of it.
The more I think of it, I feel that android TV's CEC implementation is at fault here. For example when I turn off aTV so that it shuts down all other components (via Power-off broadcast command), AVR wakes up after couple of seconds to TV input (ie the ARC). After rebooting androidTV (you need to hold power button for 5 seconds on tv remote), it corrects itself until next time.
The TV is polling the CEC bus heavily and every now and then I see bit timing errors, even with every other device disconnected. That leaves TV itself as the source of them.

Another interesting observation - Sony devices play very well between themselves on CEC. I have the TV, AVR and UHD Bluray. Never a problem, everything works, including OSD name of devices and custom functions (Bravia Sync : Control Audio System for example).

PS I could give you some of my CEC bus snoop logs, if you are interested in tracing them.

 

[HobeSoundDarryl]

CEC seems to be hit or miss in general. Some stuff works well together. Some doesn't. It's well implemented here, but not there. There is a big opportunity for some major to step in and reinvent it with a true standard imagined, documented and enforced (to have claim to the standard) in a "just works" way. The idea of it is great but the adherence & implementation is anywhere from great to terrible to N/A.

In the meantime, similar frustrations for me led to just giving up on CEC. A great alternative is a "learn" remote that can also execute custom macros. Replicate the functions of what you want CEC to do within the remote and then YOU control those functions rather than wishing programmers at completely separate companies would work to make their stuff work well with competing company's stuff.

There is no magic, "hold down these 2 buttons on this and this button on that while simultaneously plugging in this other thing." Fonzie can't show up, hit the equip in just the right place and make it all play nice together. Etc.

BUT, if you go the universal, leaning, macro remote, every CEC function can be replicated no matter what equipment one has... or may add in the future. It is the ONE best way to solve every one of these kinds of problems because it takes the interoperability out of the realm of code users can't change.

 

[PavelPr]

While I have no good solution to your problem, I can attest that my Z9D and appleTV and Arris IPTV set-top box do not play well together on CEC either.
I run all my devices via STR-DN1080 AVR, only HDMI 3 (ARC) is connected at TV.
From CEC logs I can only see, that aTV is losing it's logical address and needs to start re-acquiring it (btw hot-plugging HDMI forces this to happen as well).
Disconnecting CEC from Arris (NB! physically disconnecting HDMI pin 13, not just disabling in software) has alleviated the problem for me. At least now aTV is always responsive to CEC commands. I have not had the screen blanking issue after wakeup.
I believe in general, the codebase for A1 and Z9D is the same. I have the EU version of it.
The more I think of it, I feel that android TV's CEC implementation is at fault here. For example when I turn off aTV so that it shuts down all other components (via Power-off broadcast command), AVR wakes up after couple of seconds to TV input (ie the ARC). After rebooting androidTV (you need to hold power button for 5 seconds on tv remote), it corrects itself until next time.
The TV is polling the CEC bus heavily and every now and then I see bit timing errors, even with every other device disconnected. That leaves TV itself as the source of them.

Another interesting observation - Sony devices play very well between themselves on CEC. I have the TV, AVR and UHD Bluray. Never a problem, everything works, including OSD name of devices and custom functions (Bravia Sync : Control Audio System for example).

PS I could give you some of my CEC bus snoop logs, if you are interested in tracing them.

Thank you for your insights! I, too, had a case where a particular Technicolor cable STB was unwilling to play nice with another Sony TV I own (which is connected to a Sony STR-DH550 receiver). When one would switch the STB into standby, all CEC communication between all other devices connected to in said setup would be blocked entirely. Faced with no other choice, I ended up calling the cable operator and requesting an STB that is made by another manufacturer (Thomson), which indeed did not interfere with CEC (given my particular setup).

The possibility of deactivating pin 13 had actually crossed my mind today, before posting here. Thing is that I'm usually not a fan of these kind of creative solutions and would much rather prefer a solution that is manufacturer-sanctioned. Plus, I do like the ability to use my TV remote to control the Apple TV during use.

By the way, in what is slightly reminiscent of your description, I had one single occasion in which the receiver abruptly woke up for no apparent reason, while the TV itself remained on standby. I immediately took both the TV and Apple TV out of standby, in order to see whether this has anything to do with the issue I'm experiencing – and lo and behold, no signal detected on HDMI port 2. Unsurprisingly, the usual TV power-cycling ritual ensued thereafter.

Oddly enough, the Apple TV itself is not connected to the receiver directly. Instead, it is connected to the TV's HDMI port 2 (the TV is subsequently connected to the receiver via HDMI port 3 (ARC)). If the receiver indeed woke up because of some CEC signal generated by the Apple TV (which I cannot be sure of) – it must have passed through the TV onto the receiver (even though the TV itself, in contrast to the receiver, never woke up to that signal).

I am actually wondering how heavily my TV would poll the CEC bus during standby. I guess there is only one way to find out. Do you mind sharing the way in which you were able to obtain dumps of CEC traffic? Did you utilize any specialized hardware in order to gain access to the CEC bus?

I might need to study the HDMI CEC protocol a bit further before I could make anything meaningful out of it, but faced with no other choice – I might actually do just that.

Thanks!
[doublepost=1524687272][/doublepost]

CEC seems to be hit or miss in general. Some stuff works well together. Some doesn't. It's well implemented here, but not there. There is a big opportunity for some major to step in and reinvent it with a true standard imagined, documented and enforced (to have claim to the standard) in a "just works" way. The idea of it is great but the adherence & implementation is anywhere from great to terrible to N/A.

In the meantime, similar frustrations for me led to just giving up on CEC. A great alternative is a "learn" remote that can also execute custom macros. Replicate the functions of what you want CEC to do within the remote and then YOU control those functions rather than wishing programmers at completely separate companies would work to make their stuff work well with competing company's stuff.

There is no magic, "hold down these 2 buttons on this and this button on that while simultaneously plugging in this other thing." Fonzie can't show up, hit the equip in just the right place and make it all play nice together. Etc.

BUT, if you go the universal, leaning, macro remote, every CEC function can be replicated no matter what equipment one has... or may add in the future. It is the ONE best way to solve every one of these kinds of problems because it takes the interoperability out of the realm of code users can't change.

Yeah, it sure does appear as though CEC is a mess. In my case, vendor specific implementations have always interoperated flawlessly (I mostly buy Sony products). Yet, in what concerns pan-vendor setups, my mileage has varied.

On another note, I actually own a Logitech Harmony One remote that might be a good last resort. Counter-intuitively still, this issue starts appearing precisely when CEC-related functionality gets disabled. I am truly perplexed.

 

[HobeSoundDarryl]

Again, occasionally CEC "just works." However, pile up connected stuff and odds start rising that oddities will show themselves. Eventually one tires of trying to guess what might be the issue. You can never see the code, nor get valid answers on whether this properly works with that. Etc. The various manufacturers mostly only care if their implementation of CEC works with THEIR hardware. They generally don't give a hoot about how it work with competitor tech.

HOWEVER, pretty much everything works with RF (remotes). So leverage the much more likely-to-work technology to do whatever you wish CEC would do. For me, I just turned off CEC on the various devices. I use "one remote to rule them all" and "learning" and "macro" features allow me to control the CEC-like functionality (except that this option actually works with anything).

It's also future proof. Add something new, "learn" it's remote, update macros as needed, and it- whatever it is- will work just fine with everything else too.

Else, you find yourself chasing answers without even knowing if the question is valid. Is it a bad cable(s)? Is it a sequence of setting things up? Strangers online will both swear they have the exact same setup and it works perfectly fine for them, while other strangers will claim to have the exact same setup and it never worked for them. Try this. Try that. This worked for me. Etc. But you can never completely pin down where the actual issue lies because the actual CEC implementation is in code & functionality you can't thoroughly isolate & test. Bad cable? Bad TV? Bad receiver? Bad jacks? Wrong setup sequence? Reboot this. Restart that. No, do it in this order. No, in this order. Etc.

Basically, apply your background and give it your best shot. When you get to that point of "I've tried everything within reason," it's probably NOT going to work for you. Program the remote to be your own CEC functionality tool. Turn off CEC functionality in the various devices. Use the remote to do everything you want CEC to do... and more. It's hard to shoot a target that you can't even see.

 

[PavelPr]

Even though I'm usually not the guy to give up on things, your reasoning makes a lot of sense...

 

[HobeSoundDarryl]

Frankly, once you embrace shifting CEC-like control out this way, you quickly realize you can do so much more with it.

As to not giving up, sounds like you gave it a good try. If the ONE thing that changed was TV4 to TV4K but it otherwise "just worked" before, perhaps swap out the TV4K? However, in my experience, even though they should be very, VERY similar in code, those 2 TVs seem to have their own peculiar differences. For instance, my older 4 can "quick scroll" without issues. My much newer 4K, can only quick scroll a small number of lines, then stalls, then quick scrolls, then stalls, etc.

Perhaps it's Apple "improving" on something that "just worked"? Maybe they did the same with their CEC implementation on the newer unit?

 

[PavelPr]

To my understanding, the Apple TV 4 and 4K vary significantly in terms of chipsets. Seeing that HDR and Dolby Vision require support in both hardware and software, tvOS must treat these units differently in that regard.

Sure enough still, disabling Enhanced HDMI signal support within the TV immediately results in regained signal (albeit without HDR or Dolby Vision support). This is actually quite interesting, to be honest.

 

[priitv8]

Which HDMI ports you connect to, do not matter at all, as CEC is a single-wire bus:
https://forums.macrumors.com/thread...tv-over-hdmi-cec.1935105/page-5#post-25453637
Whoever designed this dual-addressing scheme (physical + logical), deserves a medal of bad design, imho.

To snoop (and why not also control it!), I use Pulse Eight USB - CEC Adapter.
Their software package contains a utility named cec-client which can do bus and topology snooping plus command sending from command line.

Full CEC spec you will find in SUPPLEMENT 1 of a HDMI spec. Physical address resolution you need to take from the EDID section of HDMI.

 

[henkerhaus]

Hi!

I am experiencing a very strange situation with my configuration on which I hoped somebody could shed some light.

I own a Sony KD-65A1 TV connected via its HDMI 3 (ARC) port to a Sony STR-DH770 receiver. Formerly, I used to own a 4th generation Apple TV which was connected to the TV directly and worked great.

Last Friday I went out and bought an Apple TV 4K. Having connected it directly to the TV's HDMI port 2 (not via the receiver), it initially worked fine. However, something strange happens after both devices would enter standby for a period of roughly 30 minutes or longer: once turned back on, the TV would not be able to detect any signal from the Apple TV.

The TV would be able to tell that the Apple TV is connected to it; it would also be able to specify the resolution at which the video signal is ostensibly transmitted, it would also "flicker" briefly (in what appears to be an attempt to establish connection) but no picture would appear. Both the TV and the Apple TV are updated to their respective latest software releases (TV firmware version 6.2858 and tvOS 11.3).

While experimenting with this, I've made the following observations:

1. Once the problem occurs, the only way to regain connectivity under said configuration is to either power-cycle or restart (using the "Restart" option that's under the "About" menu) the TV itself. Power-cycling just the Apple TV bears no effect;

2. In some (not all) instances, the Apple TV has to be power-cycled too as it would become non-responsive to its own remote control, wouldn't "wake up", and the only way to then regain device responsiveness is to physically unplug and re-plug its power cord;

3. Changing the HDMI cable to a more expensive one had no effect;

4. Restoring both the TV and the Apple TV to their factory defaults had no effect;

5. Once the issue manifests, connecting the Apple TV (apart from instances where it wouldn't turn on) to another HDMI port (1 or 4) would work. Likewise, connecting another device to HDMI port 2 (to which the Apple TV is usually connected) works properly as well. Moreover, disabling "Enhanced HDMI" mode on the TV results in regained connectivity, albeit without HDR or Dolby Vision support.

At this point, the only way to regain proper connectivity under the original configuration is to power-cycle or soft-restart the TV. To me, it appears as though something in the "marriage" of the Apple TV with a particular HDMI port breaks until the TV itself is power-cycled or restarted.

And then it finally dawned on me: in the Apple TV, I usually have the ability to turn on the TV with the Apple TV remote disabled ("Settings" -> "Remotes and Devices" -> "Turn On Your TV with Your Remote"). Once I re-enabled this setting, and ensured that the TV would be turned on and off via the Apple TV, the issue bizarrely disappeared. Once I turned that option back off, the issue started recurring.

Still, I am not interested in having the Apple TV control my devices in this manner and prefer to have that setting off. I have seen a variety of Apple TV 4K HDMI CEC-related issues documented on these forums, some of which were fairly similar to mine, with the exception being the fact that while other posters reported that restarting the Apple TV helps, nothing short of power-cycling the TV itself works for me. It seems as though some kind of state gets corrupted, otherwise I have no way of explaining this behavior.

Did anyone ever experience anything like this?

Thanks in advance!

I have a Sony XBR65X930E TV. I am running my AppleTV 4k through a Sony STR-DN1080 AV receiver. The receiver is connected to the TV through the HDMI 3 (ARC) port. "Enhanced HDMI" signal format is enabled on BOTH the receiver and the TV. I am running the AppleTV 4k in Dolby Vision at 60 Hz.

My comment is directed at your comment of "it would also "flicker" briefly (in what appears to be an attempt to establish connection) but no picture would appear."

Prior to the TV OS 11.3 update, which added the Dolby Vision Support, everything worked fine, but the best image format possible was HDR at 60 Hz. I was using Dynex HDMI cables from Best Buy, that were supposedly rated at 18 Gbps. These cables were fast enough to support 4k resolution, in SDR and HDR, but not fast enough to support Dolby Vision at 60 Hz. After installing the TV OS 11.3 update, when I tried to enable Dolby Vision at 60 Hz, I experienced the exact same problem. It would "flicker" briefly (in what appeared to be an attempt to establish a connection) but no picture would appear." If I reduced the format back down to HDR at 60 Hz, everything was fine.

I came to the conclusion that the HDMI cables I was using were probably just NOT fast enough to support the data stream rate required to support the Dolby Vision format at 60 Hz. So, I ordered a complete set of all new supposedly "Certified" HDMI Premium cables from AMAZON.com. I found that these "more expensive", and supposedly "certified" HDMI Premium cables didn't even work as good as the Dynex cables from Best Buy?! I now just got a Black, "No signal" screen, even on just 4k HDR 60 Hz. These cables would only support a 4k SDR signal!

So, I sent those back, and finally went ahead and ordered a complete set of Belkin's Ultra High Speed HDMI 2.1 cables, rated at 48 Gbps. As far as I know, these are the only HDMI 2.1 cables available, that are rated to support Dolby Vision at 60 Hz. After installing these cables, I was now able to get a Dolby Vision 60 Hz image (no Black, "No signal" screen anymore), but the image still had a continual intermittent flicker?! (like the image was just on the verge of being unstable). I called Apple support, and after some diagnostic testing, we determined that swapping to one of the other Belkin cables resolved the issue completely. That indicated that just the one cable from Belkin turned out to be defective. I returned the defective cable to Belkin, and they sent me a replacement. I installed the replacement, and everything works fine now.

So, the point I want make is that all HDMI cables, regardless of price, brand, or labeling, are not created equal, and even the best cable currently available can potentially be defective. The Belkin cable is what Apple recommends, and is the only cable currently rated at 48 Gbps, that specifically states that it supports Dolby Vision. At $30 each, they're not the cheapest cable out there, but they're also not the most expensive one either, and they are far less than what many other "lesser" quality/performance cables cost.

Based on my experience, I would recommend that you replace the HDMI cables with the ones that Apple recommends.
It solved this problem for me.

 

[loekf]

48 Gbps for 4K HDR 60 Hz is overkill of course, unless you want to be prepared for 120Hz and 8K what is in the HDMI 2.1 spec.

I am using these with the same setup:

https://www.allekabels.nl/hdmi-kabe...el-high-speed-met-ethernet-professioneel.html

these are 10 euros cheaper compared to the Apple/Belkin one.

 

[PavelPr]

I am still looking into this. Apple has been notified (I spoke with one of their senior support engineers).

The outcome of this regardless, I've ordered a couple of these Lindy HDMI CEC Less adapters – just to avoid the possibility of being CEC'd over looking forward.

https://www.amazon.com/Lindy-HDMI-Adapter-Female-41232/dp/B00DL48KVI

Which HDMI ports you connect to, do not matter at all, as CEC is a single-wire bus:
https://forums.macrumors.com/thread...tv-over-hdmi-cec.1935105/page-5#post-25453637
Whoever designed this dual-addressing scheme (physical + logical), deserves a medal of bad design, imho.

To snoop (and why not also control it!), I use Pulse Eight USB - CEC Adapter.
Their software package contains a utility named cec-client which can do bus and topology snooping plus command sending from command line.

Full CEC spec you will find in SUPPLEMENT 1 of a HDMI spec. Physical address resolution you need to take from the EDID section of HDMI.

Thanks a lot! I might give this a try if nothing else helps.
[doublepost=1524907134][/doublepost]

I have a Sony XBR65X930E TV. I am running my AppleTV 4k through a Sony STR-DN1080 AV receiver. The receiver is connected to the TV through the HDMI 3 (ARC) port. "Enhanced HDMI" signal format is enabled on BOTH the receiver and the TV. I am running the AppleTV 4k in Dolby Vision at 60 Hz.

My comment is directed at your comment of "it would also "flicker" briefly (in what appears to be an attempt to establish connection) but no picture would appear."

Prior to the TV OS 11.3 update, which added the Dolby Vision Support, everything worked fine, but the best image format possible was HDR at 60 Hz. I was using Dynex HDMI cables from Best Buy, that were supposedly rated at 18 Gbps. These cables were fast enough to support 4k resolution, in SDR and HDR, but not fast enough to support Dolby Vision at 60 Hz. After installing the TV OS 11.3 update, when I tried to enable Dolby Vision at 60 Hz, I experienced the exact same problem. It would "flicker" briefly (in what appeared to be an attempt to establish a connection) but no picture would appear." If I reduced the format back down to HDR at 60 Hz, everything was fine.

I came to the conclusion that the HDMI cables I was using were probably just NOT fast enough to support the data stream rate required to support the Dolby Vision format at 60 Hz. So, I ordered a complete set of all new supposedly "Certified" HDMI Premium cables from AMAZON.com. I found that these "more expensive", and supposedly "certified" HDMI Premium cables didn't even work as good as the Dynex cables from Best Buy?! I now just got a Black, "No signal" screen, even on just 4k HDR 60 Hz. These cables would only support a 4k SDR signal!

So, I sent those back, and finally went ahead and ordered a complete set of Belkin's Ultra High Speed HDMI 2.1 cables, rated at 48 Gbps. As far as I know, these are the only HDMI 2.1 cables available, that are rated to support Dolby Vision at 60 Hz. After installing these cables, I was now able to get a Dolby Vision 60 Hz image (no Black, "No signal" screen anymore), but the image still had a continual intermittent flicker?! (like the image was just on the verge of being unstable). I called Apple support, and after some diagnostic testing, we determined that swapping to one of the other Belkin cables resolved the issue completely. That indicated that just the one cable from Belkin turned out to be defective. I returned the defective cable to Belkin, and they sent me a replacement. I installed the replacement, and everything works fine now.

So, the point I want make is that all HDMI cables, regardless of price, brand, or labeling, are not created equal, and even the best cable currently available can potentially be defective. The Belkin cable is what Apple recommends, and is the only cable currently rated at 48 Gbps, that specifically states that it supports Dolby Vision. At $30 each, they're not the cheapest cable out there, but they're also not the most expensive one either, and they are far less than what many other "lesser" quality/performance cables cost.

Based on my experience, I would recommend that you replace the HDMI cables with the ones that Apple recommends.
It solved this problem for me.

Thank you for your incredibly detailed comment!

My situation is different from yours in that I am able to watch content on the Apple TV 4K for hours and hours, in Dolby Vision, without a single loss of signal. For whatever reason, however, after a period of standby, sometimes hell would break loose.

I am using a top-of-the-line Audioquest HDMI cable, but previously I did try other cables, with one of them even being Apple-branded. I actually have a Belkin cable lying around here somewhere, probably connecting some other device. I might actually give it a try, to rule out the slightest possibility of this being "a kind of magic"...

P.S. I've updated my initial post with a more recent finding.

Thank you again!

 

[Mrbobb]

Oh God, sounds like HDMI 1.0 again... will let you guys work out the kinks first, staying with my boring 1080p. Why do I get the feeling when they designed this HDMI thing, it was half-baked.

 

[cube]

HDMI CEC gives me trouble between my TV and receiver, so I switch it off in the menus.

 

[PavelPr]

HDMI CEC gives me trouble between my TV and receiver, so I switch it off in the menus.

The best way to describe CEC is a hit and miss, like HobeSoundDarryl said. In my experience, CEC-wise, Sony products (TVs and receivers, in particular) interoperate flawlessly. Still, said idyll may change once devices made by other vendors are introduced into the system. When that happens, one's mileage may vary and the root cause cannot always be easily isolated.

One could reasonably expect the mess surrounding CEC to be mitigated over time, but reality is obviously very different.

 

[cube]

In my experience, CEC-wise, Sony products (TVs and receivers, in particular) interoperate flawlessly. Still, said idyll may change once devices made by other vendors are introduced into the system. When that happens, one's mileage may vary and the root cause cannot always be easily isolated.

I would imagine this is also true for other major ecosystems.

 

[BODYBUILDERPAUL]

I have a Sony XBR65X930E TV. I am running my AppleTV 4k through a Sony STR-DN1080 AV receiver. The receiver is connected to the TV through the HDMI 3 (ARC) port. "Enhanced HDMI" signal format is enabled on BOTH the receiver and the TV. I am running the AppleTV 4k in Dolby Vision at 60 Hz.

My comment is directed at your comment of "it would also "flicker" briefly (in what appears to be an attempt to establish connection) but no picture would appear."

Prior to the TV OS 11.3 update, which added the Dolby Vision Support, everything worked fine, but the best image format possible was HDR at 60 Hz. I was using Dynex HDMI cables from Best Buy, that were supposedly rated at 18 Gbps. These cables were fast enough to support 4k resolution, in SDR and HDR, but not fast enough to support Dolby Vision at 60 Hz. After installing the TV OS 11.3 update, when I tried to enable Dolby Vision at 60 Hz, I experienced the exact same problem. It would "flicker" briefly (in what appeared to be an attempt to establish a connection) but no picture would appear." If I reduced the format back down to HDR at 60 Hz, everything was fine.

I came to the conclusion that the HDMI cables I was using were probably just NOT fast enough to support the data stream rate required to support the Dolby Vision format at 60 Hz. So, I ordered a complete set of all new supposedly "Certified" HDMI Premium cables from AMAZON.com. I found that these "more expensive", and supposedly "certified" HDMI Premium cables didn't even work as good as the Dynex cables from Best Buy?! I now just got a Black, "No signal" screen, even on just 4k HDR 60 Hz. These cables would only support a 4k SDR signal!

So, I sent those back, and finally went ahead and ordered a complete set of Belkin's Ultra High Speed HDMI 2.1 cables, rated at 48 Gbps. As far as I know, these are the only HDMI 2.1 cables available, that are rated to support Dolby Vision at 60 Hz. After installing these cables, I was now able to get a Dolby Vision 60 Hz image (no Black, "No signal" screen anymore), but the image still had a continual intermittent flicker?! (like the image was just on the verge of being unstable). I called Apple support, and after some diagnostic testing, we determined that swapping to one of the other Belkin cables resolved the issue completely. That indicated that just the one cable from Belkin turned out to be defective. I returned the defective cable to Belkin, and they sent me a replacement. I installed the replacement, and everything works fine now.

So, the point I want make is that all HDMI cables, regardless of price, brand, or labeling, are not created equal, and even the best cable currently available can potentially be defective. The Belkin cable is what Apple recommends, and is the only cable currently rated at 48 Gbps, that specifically states that it supports Dolby Vision. At $30 each, they're not the cheapest cable out there, but they're also not the most expensive one either, and they are far less than what many other "lesser" quality/performance cables cost.

Based on my experience, I would recommend that you replace the HDMI cables with the ones that Apple recommends.
It solved this problem for me.

I agree buy the APPLE RECOMMENDED LEAD! I really cannot understand why people aren't buying the RECOMMENDED HDMI lead from Apple. It's been designed from day one to work with the ATV 4K. It's crazy that people spend £2000++++++++ on a TV and set up and complain about a 30 dollar lead which is only bought once! I just don't understand. Surely, if Apple recommends ONE particular lead to work with the ATV 4k 100% of the time, then you simply buy it at the time of buying the ATV?????????? I've always bought the Apple recommended HDMI leads from the ATV 2, 3, 4 to 4K and i've never had an issue. Ever.

It's as though some people think that they know more than the actual people at Apple who are designing and implementing this tech.