Flickering vertical lines on M1 Mac Mini

[billpaxton]

Well, at least Apple is consistent. Just ask any Mac Pro Trashcan owner with burnt-out graphics cards or anyone with a butterfly keyboard laptop.

I just got rid of my 2016 MBP with display and keyboard issues. this one is thankfully software 😅

 

[xoxmx]

I have bought the a new Mac mini M1 and I have the same issues. I am already on a second monitor, returned a Dell P2721Q and bought a BenQ PD2700U and the problem still persists. It is not cable related. I have tried HDMI to HDMI, USB-C to USB-C (Dell), 8k cable bought separately for the BenQ (USB-C to DP). Only happened to me when browsing Safari, certain images trigger this problem.

 

[harrisonjr98]

I have bought the a new Mac mini M1 and I have the same issues. I am already on a second monitor, returned a Dell P2721Q and bought a BenQ PD2700U and the problem still persists. It is not cable related. I have tried HDMI to HDMI, USB-C to USB-C (Dell), 8k cable bought separately for the BenQ (USB-C to DP). Only happened to me when browsing Safari, certain images trigger this problem.

For me, whenever I have a webpage causing the issue I can usually "solve" it by scrolling down, and then cause it to happen again by scrolling back up. Is it the same for you?

 

[xoxmx]

For me, whenever I have a webpage causing the issue I can usually "solve" it by scrolling down, and then cause it to happen again by scrolling back up. Is it the same for you?

Yes, exactly.

 

[mabok]

For me, whenever I have a webpage causing the issue I can usually "solve" it by scrolling down, and then cause it to happen again by scrolling back up. Is it the same for you?

yup i think everyone else is like that. mine too. i sometimes experience it on spotify app on a mac.
it's like if there's a gradient of grey, black, will have it. I still cannot pin point which specific area will cause the flicker.

I sometimes leave the flicker for quite a while and it ends up leave a burn in effect when I switch to other webpage or other apps. But it will be back to normal after a few secs or so.

 

[Crackman]

yup i think everyone else is like that. mine too. i sometimes experience it on spotify app on a mac.
it's like if there's a gradient of grey, black, will have it. I still cannot pin point which specific area will cause the flicker.

I sometimes leave the flicker for quite a while and it ends up leave a burn in effect when I switch to other webpage or other apps. But it will be back to normal after a few secs or so.

same problem here, I also left it flickering for a while and the burnin even persisted on other monitor inputs. I unplugged the Mac mini from the monitor but the burnin was still there on my windows pc input. After a power cycle, burnin still there. After I let it sit for a while, the burnin slowly goes away.
This is definitely very strange behaviour..

 

[mabok]

Hmmm. I just tried switch display resolution from 4k to 2560 x 1440 (lower resolution) or without (lower resolution) option... and it works. No more flickering usually if there's black, dark colours, dark greys on the screen.

Normally when I view netflix on web browser (Safari, etc) there's a certain area will cause the flicker. But now no more.
Might be temporary. I really hope this is software issues...

 

[therealRJP]

Has anyone noticed if this persists in the OS12 beta?

 

[jehy]

Has anyone noticed if this persists in the OS12 beta?

I can confirm this still exists in MacOS 12.0 Monterey, I upgraded to the beta hoping to find it'd been fixed... sadly not.
I contacted Apple Support and asked them about the problem, pointed out it's very well documented... they of course tried to make out they'd not heard of this issue before! Better still they wouldn't discuss further as I was running the beta, they suggested I downgrade before they could assist with troubleshooting further....even though they'll know it's a known issue, with no fix.

 

[mziaeem]

I solved this issue by changing the refresh rate from 60 to 50.
If you want to solve this issue completely, switch to the 30hz refresh rate or switch to low-resolution mode.
I think that m1 can not generate stable 4k 60Hz signal.

 

[xoxmx]

I can confirm this still exists in MacOS 12.0 Monterey, I upgraded to the beta hoping to find it'd been fixed... sadly not.
I contacted Apple Support and asked them about the problem, pointed out it's very well documented... they of course tried to make out they'd not heard of this issue before!

This is actually really bad! I was hopping for a fix with the next update. I still do not understand why nobody from the industry or from tech media has covered this. Here is my video from today. This is getting really annoying.

 

[xoxmx]

I solved this issue by changing the refresh rate from 60 to 50.
If you want to solve this issue completely, switch to the 30hz refresh rate or switch to low-resolution mode.
I think that m1 can not generate stable 4k 60Hz signal.

Actually, I will not. I have bought the Mac Mini M1 because it should handle 60hz 4K signal. I am not going 10 years back in time. I would love to see a fix by Apple or bear the consequences for false advertising.

 

[mziaeem]

Actually, I will not. I have bought the Mac Mini M1 because it should handle 60hz 4K signal. I am not going 10 years back in time. I would love to see a fix by Apple or bear the consequences for false advertising.

I've also purchased M1 for 4k support and IOS apps support. Unfortunately, m1 has failed on 4k rendering, and Apple restricts usage of IOS apps in the latest version. So I've wasted my money. My old Windows laptop was handling other stuff very well.
This problem probably is hardware-related. Apple has made a huge profit by selling M1 macs. so I think he would never confirm this problem and never solve it.

 

[ZA WARUDO]

edit: wrong theme, del pls

 

[Sarah Hamilton]

I apologize for the triple post, but there's an interesting development I wanted to share (and it's quite a big one, completely unrelated to the previous post).

I've found (ordered, received and tested) a USB-powered HDMI 2.0 (with 4K@60Hz support) HDMI splitter on Amazon/eBay which does exactly two things:
1) Pretends to be a 4K & HDR-enabled 52" display (it can also pretend to be a 1080p display or pass through your monitor's EDID to the Mac, but it'd defeat the purpose of the exercise)
2) Downscales the 4K input to 1080p. Since the Mac now thinks it's connected to a 4K display, it also turns on HiDPi scaling settings (like on a MacBook's internal screen - "More Space" and stuff like that instead of numerical resolutions, basically).

Pros:
1) 4K supersampling for my PS5 (not sure whether it does so for every game on 1080p, but it will be forced to do so).
2) Presents an EDID of a screen with speakers! My Mac and my gaming consoles are connected to a 4x1 HDMI switch with a built-in audio extractor. I plug my headphones into it when I play console games since they just assume that the screen has audio support, however, I have to plug the headphones back into the Mac itself when going back to the computer since the Mac knows my monitor doesn't have speakers (when I was using a different monitor with speakers on it with my old Mac, this extractor worked fine, so it's definitely an EDID thing). Well, not anymore! I can now select the monitor as an audio output even though it doesn't have speakers.
3) Why we're all here: seems to fix my shimmering/flickering issues in grey colored areas / light colored issues. I think the issue originated from EDID or HDMI handshaking issues, which are probably resolved by this device. http://color.aurlien.net/ is the site I used to test all sorts of colors and so far wasn't able to see any shimmer/flicker on any of the color profiles I've tried.
4) Can't feel any additional latency when using the OS (can't comment on gaming results, didn't have a chance to check it out yet, just that the PS5 works with the device at all).

Cons:
1) It costs money (about $30) - a GPU driver update is free and isn't a workaround that involves extra cables and extra power.
2) An active device, requires 5V@some probably pretty low amperage of power (delivered through a Micro USB cable that's included in the box and either your Mac's USB port or a phone charger, there isn't one in the box though - just like with a new iPhone! lol)
3) Was hard to get it to work initially (my monitor was saying "input not supported" when using my Mac, worked fine with my PS5). The issue was with my Kingston USB C hub, turns out: when plugged into the Mac mini itself it works okay (Mac mini -> HDMI switch -> HDMI splitter -> monitor). I'll blame this on my hub, though.
4) Likely doesn't downscale to 1440p, effectively making it useless as a HiDPi solution (I don't really see a point of HiDPi on a 1080p screen, though maybe it's just me). It's either 4K or 1440p at the output, no in-between. Now, there's a firmware update tool (I haven't checked it but chances are it's a CLI windows-only tool, not sure though, I'll update this post if it's a Mac-compatible thing, but I reeeeally doubt it) and some comments indicate that the manufacturer actually listens to feature requests, so in case the output can be reconfigured programmatically to 1440p (meaning if the output circuitry supports it, which I just don't know a way of telling, I don't feel like opening it up) then maybe one can request to replace the 1080p downscaling to 1440p downscaling. Overall, I'd suggest you do your own research into this, I didn't really look into 1440p support since I have no use for it personally.
5) Affects the color calibration/colors in general ever so slightly. I'd say it's a very minor and a barely perceptible effect, but if you work with graphics/colors professionally, it's a different thing - I'm not confident suggesting this to you, in such a case.


What I'm unable to test:
1) The color space (RGB or not) - my cheap monitor doesn't show the kind of input it's getting
2) HDR - PS5 recognizes my monitor as HDR-capable (so does the Mac) and that's about it, obviously the results look washed out if I turn it on
3) High refresh rate / variable refresh rate: again, I only have a simple 1080p@60Hz AOC monitor so I can't check.
4) 1440p - see above.

https://www.amazon.com/gp/product/B07VP37KMB/

The link is for the device that I bought (non-affiliated link, if anyone cares, I'm just a guy on a forum), however it seems to be a generic Chinese scaler/splitter I think? I did get an ad for the same thing from a different manufacturer (I guess it just had a different logo and a different distributor but was made in the same factory, idk) and it was a dollar or two cheaper but had longer shipping so you might want to do some research. One of the comments in the Q&A section from the manufacturer says that it doesn't work with only 1 video output but it works fine for me.

For reference, I'm using a 4:4:4 HDMI 2.0 (4k@60Hz-supporting) HDMI switch and 3 decent cables (all support 18Gbps, should be enough for 4K@60 and it looks like it works fine).

I'll update this post if I notice the shimmer somewhere again, but so far it seems to be fine. I have no skin in the game so if the device doesn't work for you for some reason - I'm sorry, just sharing my (n = 1) success story here and I can't guarantee it'll help your case.
If y'all have any questions or want me to test something/record a video/etc - do tell, I'll try to find a minute in the next couple of days.

EDIT: it seems that the downscaler makes the overall image a smidge softer than it is when I connect directly to the Mac, not sure whether it is actually the case or just my feeling. It now looks like the output I used to get from my Intel MBP (2017) that I traded in for this M1 mini. I don't think staring at my monitor up close in glasses is a normal use case, so with around 2 feet between my face and the screen it looks just fine.

EDIT 2: using M1MacTimings.sh (a script I found on GitHub) I found a curious thing with this device - my monitor is now treated as disp0 (not dispext0). Not sure what's up here - maybe it's just that I stopped using a USB C hub, not entirely certain. 2048x1152 also seems like a good resolution for a 1080p monitor (everything is ever-so-slightly smaller, but not to a point where the text becomes less readable in any significant way).

EDIT 3: after messing around with it some more and using RDM I've been able to verify that I still have the shimmer/flickering when using the default 1080p@60Hz mode (not downscaled from 4K). This splitter, however, allows me to access a 1080p@59.94Hz mode, which I'd expect to look identical to the previous one - yet it doesn't. It resolves 99% of the flicker for me. The final 1080p mode available is a downscaled 4K (using HiDPI) - it has deeper blacks (which might actually be a bit of a detriment, not sure yet) and slightly blurrier fonts. These fonts are what I'm used to since they look like what I'd get from my old MBP. The native M1 output is noticeably sharper and has better font rendering, sure, but it also produces the unpleasant artifacts which are really distracting. I have to say that light mode works a lot better than dark mode when using this output type (I didn't use dark mode on my MBP with this monitor due to blurry fonts as well). I have to conclude that most likely my MBP was performing the same HiDPI downscaling behind the scenes, since the output looks so similar. The downscaling process itself might also be a kind of a low-pass filter in a way, masking the high-frequency (in terms of pixel density, I guess? not really sure what's the best way to say this) noise/flicker. That's all I have for now.

FINAL EDIT: Well, not sure what to think after using this adapter for a few days. I feel like my Mac is ever so slightly warmer (rendering @ 4K and downscaling vs rendering natively = additional CPU/GPU load)and the screen contrast is a little off (I prefer the way it looks with my PS5, but that's a personal thing). I guess my final educated guess of a conclusion will be that the downscaling process (4K->1080p) acts as a low-pass filter (meaning that the noise is likely still present in the 4K signal that the Mac outputs, but gets lost when downscaling the signal because the size of the noise in pixels is really small). I'd say that this still makes the screen somewhat easier on the eyes (the flicker was really unpleasant), but obviously doesn't eliminate the issue. I think that this is definitely an M1 issue (see marts2007's video below), hopefully something GPU driver-related (since rendering itself works fine, as demonstrated by using SideCar and not having those issues on my iPad's screen), and I'm hoping Apple fixes it soon - I can't afford to return or exchange it for now and I otherwise prefer this to my previous Mac.
I'm also going to keep this splitter (after all, the device itself is not faulty and at some point might come in handy for other uses to me), but I don't recommend you get it as a solution to this problem - only buy it if you're up to trying a new approach without a promise of the problem being solved, which is a shaky value proposition at thirty bucks I'd say.

No one should have to go through major diagnostics like this. This device has a HDMI port, it should plug and play with a HDMI display (albeit selecting resolutions and refresh rates is understandable).

Today the Apple Support representative let me know that Apple engineers were able to recreate the issue I'm having (which is likely the same as the one that's described in this thread) using the same monitor as I'm using and are going to work on it for a future software update. They were originally going to get me to send my Mac in for testing, but it wasn't necessary in the end.
So here's hoping it gets fixed in 11.4, I guess! I'll be checking beta release notes and might try updating a couple of betas down the line.

It's October 2021, and I purchased the 8gb 256gb mac mini m1, and got this flickering. I am now accepting that this is a manufacturing defect, and Apple should announce some repair program. Like they did with the keyboard on the newly redesigned mbps in 2016.

For me, whenever I have a webpage causing the issue I can usually "solve" it by scrolling down, and then cause it to happen again by scrolling back up. Is it the same for you?

That is not a solve

I've also purchased M1 for 4k support and IOS apps support. Unfortunately, m1 has failed on 4k rendering, and Apple restricts usage of IOS apps in the latest version. So I've wasted my money. My old Windows laptop was handling other stuff very well.
This problem probably is hardware-related. Apple has made a huge profit by selling M1 macs. so I think he would never confirm this problem and never solve it.

I agree with the profit

 

[harrisonjr98]

No one should have to go through major diagnostics like this. This device has a HDMI port, it should plug and play with a HDMI display (albeit selecting resolutions and refresh rates is understandable).


It's October 2021, and I purchased the 8gb 256gb mac mini m1, and got this flickering. I am now accepting that this is a manufacturing defect, and Apple should announce some repair program. Like they did with the keyboard on the newly redesigned mbps in 2016.

That is not a solve

I agree with the profit

I have only heard this problem described on the M1 mini. wonder if it happens on the Air/Pro via HDMI over thunderbolt (or on the built in display for that matter.)

 

[Sarah Hamilton]

I have only heard this problem described on the M1 mini. wonder if it happens on the Air/Pro via HDMI over thunderbolt (or on the built in display for that matter.)

Only seems to be happening with external displaysb

 

[harrisonjr98]

Only seems to be happening with external displaysb

Have to wonder if anyone's noticed it on the new M1 Pro/Max chips yet.

 

[SilentProtagonist]

I have only heard this problem described on the M1 mini. wonder if it happens on the Air/Pro via HDMI over thunderbolt (or on the built in display for that matter.)

***I MAY HAVE A VIABLE WORKAROUND***

I'm here because I have this issue with a newish Macbook Air 2020 M1. I've had the Air for about two months, but a few weeks ago upgraded to a nicer 4k monitor (DELL S3221QS), and voila, I have this issue.

I'm using the Apple multiport adapter - the one with usb-c charging, hdmi port, and usb port.
I've tried multiple HDMI cables including 8k cables.
I've tried my windows laptop on the same monitor, it has no issue.
I've tried the Air on my 4k TV, it does not have the issue on the TV with the same res and refresh rate.
I tried contacting apple support and they have directed me to take the thing in to the Apple store for them to look at it. I'm not optimistic about that accomplishing anything though since it appears to manifest only on certain monitors, according to this thread, and I'm not hauling this monitor into the apple store.

Anyway, all that is preaching to the choir. I have however found a sort-of-fix that makes it tolerable for me. Try turning HDR on, in display preferences. Be prepared though -- it's going to initially make your desktop look like hot garbage! You can probably lessen the effect by going into your monitor's menu and experimenting with different HDR presets or picture presets.

HDR mode might not be tolerable to you for normal application-type work, and it's not really meant for that afaik. However if it does eliminate your flashing bars, HDR mode is great for gaming and for watching HDR video.

 

[Sarah Hamilton]

***I MAY HAVE A VIABLE WORKAROUND***

I'm here because I have this issue with a newish Macbook Air 2020 M1. I've had the Air for about two months, but a few weeks ago upgraded to a nicer 4k monitor (DELL S3221QS), and voila, I have this issue.

I'm using the Apple multiport adapter - the one with usb-c charging, hdmi port, and usb port.
I've tried multiple HDMI cables including 8k cables.
I've tried my windows laptop on the same monitor, it has no issue.
I've tried the Air on my 4k TV, it does not have the issue on the TV with the same res and refresh rate.
I tried contacting apple support and they have directed me to take the thing in to the Apple store for them to look at it. I'm not optimistic about that accomplishing anything though since it appears to manifest only on certain monitors, according to this thread, and I'm not hauling this monitor into the apple store.

Anyway, all that is preaching to the choir. I have however found a sort-of-fix that makes it tolerable for me. Try turning HDR on, in display preferences. Be prepared though -- it's going to initially make your desktop look like hot garbage! You can probably lessen the effect by going into your monitor's menu and experimenting with different HDR presets or picture presets.

HDR mode might not be tolerable to you for normal application-type work, and it's not really meant for that afaik. However if it does eliminate your flashing bars, HDR mode is great for gaming and for watching HDR video.

Can you share a photograph of how it looks with HDR just so I can understand? I'm using my 2016 MBP with my s2817q dell and it works flawless... makes me think its an M1 thing...

 

[SilentProtagonist]

Can you share a photograph of how it looks with HDR just so I can understand? I'm using my 2016 MBP with my s2817q dell and it works flawless... makes me think its an M1 thing...

I think a photo would not demonstrate this very well. HDR will make your monitor a lot brighter overall, to create more contrast between light and dark. Bright colors will look extremely vivid. Desktop programs are not made for this sort of display, so they might be hard to look at due to the brightness. Your monitor might have some HDR preset modes that would reduce the harshness. When it comes to movies and games, the HDR setting actually looks great most of the time, because most high-def content is mastered to be displayed that way.

It's easy to try it out: System Preferences > Displays > check the HDR box.
The screen may go dark for a few seconds as it switches over. If it looks like garbage, like I said try the monitor settings before you decide whether or not it can work for you.

 

[Sarah Hamilton]

I think a photo would not demonstrate this very well. HDR will make your monitor a lot brighter overall, to create more contrast between light and dark. Bright colors will look extremely vivid. Desktop programs are not made for this sort of display, so they might be hard to look at due to the brightness. Your monitor might have some HDR preset modes that would reduce the harshness. When it comes to movies and games, the HDR setting actually looks great most of the time, because most high-def content is mastered to be displayed that way.

It's easy to try it out: System Preferences > Displays > check the HDR box.
The screen may go dark for a few seconds as it switches over. If it looks like garbage, like I said try the monitor settings before you decide whether or not it can work for you.

I don't have the HDR option

 

[harrisonjr98]

It's easy to try it out: System Preferences > Displays > check the HDR box.

I could be wrong, but I believe this option only appears if your monitor is compliant with Vesa DisplayHDR certification.

 

[HosseinSh]

Solution: I also had this problem, and it got much worse after the update to Monterey.
1. The first thing I did was set the picture mode to standard in the monitor settings.
2. And the second thing I did was connect the monitor to mac mini with an HDMI cable and a USB-C HDMI converter.

 

[v0n]

None of it helped my issue so far. And yes - Monterey made it much worse. I'm already on HDMI (from USB-C), and it still happens - I can trigger it every single time if I start uploading any video to YT via YT Studio page in Firefox. And then it's bad, screen unreadable for minutes until it settles down.

Has anyone found proper solution or should I be thinking about returning this POS. This whole experience with Apple Silicon is becoming garbage. Almost no software and plugins ported, memory leaks of epic proportions (constant 10Gb of RAM used with next to nothing open), that leads to unstable FCPX either not rendering things or shutting down plugins one by one with "plugin stopped responding". Add to that regular unscheduled breaks from work when the screen goes tits up and I'm ready to be angry. It's been months and the whole experience is just getting worse.