Mac mini 2018 to LG 4K OLED55B8PLA

shamhead

macrumors newbie
Original poster
Nov 24, 2018
5
2
Hey everyone,
Is anyone else having trouble connecting the new Mac mini to a 4K tv over hdmi?

I have a LG OLED55B8PLA which is great and the mini did show on screen for a few minutes when I was setting it up then just cut off and I can’t get it to appear at all over HDMI, no signal.

When I VNC in I see in the preferences that the Mac recognised it is connected to an LG tv, but no picture!

Any help appreciated.

Also is this a trend? I am also have severe difficulties connecting my MacBook Pro 2018 to my 4K monitor.

Remember the good old days when a cable simply worked?! Haha
 
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570934

Suspended
May 3, 2011
710
101
Hey everyone,
Is anyone else having trouble connecting the new Mac mini to a 4K tv over hdmi?

I have a LG OLED55B8PLA which is great and the mini did show on screen for a few minutes when I was setting it up then just cut off and I can’t get it to appear at all over HDMI, no signal.

When I VNC in I see in the preferences that the Mac recognised it is connected to an LG tv, but no picture!

Any help appreciated.

Also is this a trend? I am also have severe difficulties connecting my MacBook Pro 2018 to my 4K monitor.

Remember the good old days when a cable simply worked?! Haha

Funny, I had the exact same issue. Even spent a load of time on the phone with Apple. Simple fix, move your HDMI sockets about as it appears to put the HDMI socket into a state which the TV can't display. You can reset the ports but saw conflicting info so just swapped my xbox and mac mini about so I didn't lose all my picture setting for the ATV :D
 

djc6

macrumors 6502a
Aug 11, 2007
570
123
Cleveland, OH
Have you tried firmware update on the TV? I got an LG TV last night, prompted for a firmware update a few minutes after connecting ethernet cable to TV
 
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shamhead

macrumors newbie
Original poster
Nov 24, 2018
5
2
Hey guys,
Unfortunately did a full factory reset and changed hdmi slots with no luck :( tv is also fully updated to the max.

Ugh, finding this incredibly frustrating, bought our first Mac mini for the living room in 2006 and thought this would be a lovely seamless upgrade to 4K. Seems I was wrong.

Any other opinions appreciated.

Cheers!
[doublepost=1543102743][/doublepost]Lol not 2006, 2011. Bit confused there
[doublepost=1543102833][/doublepost]Lol 2011 Mac mini, not 2006, bit of a decade leap there.
 

appl_core

macrumors newbie
Nov 24, 2018
3
1
Having the same exact thing happen. Unfriggin real.

Everything works IF and only if I don't change the display settings at all in the system preferences. If I adjust the output to the TV it goes blank and there is NO way to get it back other than reinstall the software. This was through a lot of trial and error. I finally added screen share so I could go into the computer with a laptop. Once the screen goes blank there is no way to reset it. Resetting it will just revert back to the new blank setting that isn't default. Even restarting. I tried putting it back to how I found it, and all of the recovery methods won't work because they also adjust the screen resolution.

Warning to anyone with an LG OLED 4K TV. DO NOT TOUCH THE DISPLAY PREFERENCES. It will render the machine useless. I have to go to a neighbors house to use their TV and get it back up and running. This only happens with my C7 OLED and not a comparable Sony. I talked to Apple and they suggested the TV firmware update which I did and it still is a problem. Obviously something is getting triggered in the OS on this machine.

Very disappointed. I realize this is a "new" version but I never had a hiccup like this on my 2014. And I used the same TV.
 
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shamhead

macrumors newbie
Original poster
Nov 24, 2018
5
2
Having the same exact thing happen. Unfriggin real.

Everything works IF and only if I don't change the display settings at all in the system preferences. If I adjust the output to the TV it goes blank and there is NO way to get it back other than reinstall the software. This was through a lot of trial and error. I finally added screen share so I could go into the computer with a laptop. Once the screen goes blank there is no way to reset it. Resetting it will just revert back to the new blank setting that isn't default. Even restarting. I tried putting it back to how I found it, and all of the recovery methods won't work because they also adjust the screen resolution.

Warning to anyone with an LG OLED 4K TV. DO NOT TOUCH THE DISPLAY PREFERENCES. It will render the machine useless. I have to go to a neighbors house to use their TV and get it back up and running. This only happens with my C7 OLED and not a comparable Sony. I talked to Apple and they suggested the TV firmware update which I did and it still is a problem. Obviously something is getting triggered in the OS on this machine.

Very disappointed. I realize this is a "new" version but I never had a hiccup like this on my 2014. And I used the same TV.


Ugh, glad to know it’s not just me but what a ridiculous scenario, will do a full reinstall and never go near the display settings. Which is annoying as scaling would be ideal on a 4K tv, in fact it might make it unusable for a living room setup.

Might have to return it!
[doublepost=1543142091][/doublepost]
Actually you are right about setting hdr on the port. This is how I ended up getting it back on using the original port.
Thanks, Yea tried that and they are all switched off.
[doublepost=1543145049][/doublepost]Actually turning the hdr on did work! Thanks
 

570934

Suspended
May 3, 2011
710
101
Ugh, glad to know it’s not just me but what a ridiculous scenario, will do a full reinstall and never go near the display settings. Which is annoying as scaling would be ideal on a 4K tv, in fact it might make it unusable for a living room setup.

Might have to return it!
[doublepost=1543142091][/doublepost]

Thanks, Yea tried that and they are all switched off.
[doublepost=1543145049][/doublepost]Actually turning the hdr on did work! Thanks
Yes turning it on helps. You can use scaling after that too so your desktop isn't so huge. Also in TV setting make sure it's set to PC too.
 
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Fishrrman

macrumors P6
Feb 20, 2009
17,170
5,526
You're using a USB-c (Mini) to HDMI 2.0 adapter (TV), is this correct?
(the "2.0" is important).

You have a "high-speed" HDMI cable between the adapter and tv, is this correct?

You're using the HDMI 2.0 port on the tv, correct?

You've got the settings (on the tv) for HDMI 2.0? (not sure about this).
 
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appl_core

macrumors newbie
Nov 24, 2018
3
1
[doublepost=1543145049][/doublepost]Actually turning the hdr on did work! Thanks[/QUOTE]

Just to confirm turning on hdr does allow you to scale?
 

570934

Suspended
May 3, 2011
710
101
[doublepost=1543145049][/doublepost]Actually turning the hdr on did work! Thanks
Just to confirm turning on hdr does allow you to scale?[/QUOTE]

Yes it does, it's just something along the colour profile which is cocking things up. Turning HDR on does cure the problem.
[doublepost=1543163211][/doublepost]
You're using a USB-c (Mini) to HDMI 2.0 adapter (TV), is this correct?
(the "2.0" is important).

You have a "high-speed" HDMI cable between the adapter and tv, is this correct?

You're using the HDMI 2.0 port on the tv, correct?

You've got the settings (on the tv) for HDMI 2.0? (not sure about this).
HDMI to HDMI so nothing to do with the usb-s
 

Fishrrman

macrumors P6
Feb 20, 2009
17,170
5,526
Cell wrote:
"HDMI to HDMI so nothing to do with the usb-s"

Yes I realize that.
But... I'm wondering if the problems can be solved by using a USB-c to HDMI 2.0 adapter in combination with a high-speed HDMI connecting cable.
 

570934

Suspended
May 3, 2011
710
101
Cell wrote:
"HDMI to HDMI so nothing to do with the usb-s"

Yes I realize that.
But... I'm wondering if the problems can be solved by using a USB-c to HDMI 2.0 adapter in combination with a high-speed HDMI connecting cable.
Just turning HDR on the HDMI channel fixes it :D Or resetting the HMDI channel. It's a bit weird I know that. Never come across this type of issue before and I work in media production.
 

ElectronGuru

macrumors 65816
Sep 5, 2013
1,492
360
Oregon, USA
Wow Can’t believe that worked. What a dumb fix.
What exactly worked, a usbc dongle? And thank you for early adoptering this. I expect to go down this road myself in a few years. Feels like Apple is expecting everyone to at4k for this application.

Edit
Seeing similar reports from hdmi to displays. Could be the port itself

So my USB-C to displayport cable arrived today. And indeed the results are much better. The original problem doesn't seem to be there, though there is a different problem now. Computer doesn't go to sleep every time.

Here is the summary -
1. On HDMI - Upon waking from sleep, computer wakes up with blank screen. Usually takes minutes for image to come up (if it does). Disconnecting and connecting the HDMI cable usually fixes it (it may take a couple of tries). Sometimes USB mouse doesn't work on waking from sleep. Disconnecting and reconnecting fixes it.
2. On Displayport (via thunderbolt port) - Computer wakes up as expected, and monitor instantly shows image. However, computer doesn't go to sleep every time. Sometimes monitor just comes back up. It may take a couple of tries to put computer to sleep. No USB mouse freezing thus far, but that's inconclusive.
 
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