M1/M2 flickering, ghosting with external display [Merged]

[awwmikheev]

I have Dell Alienware AW2521HFL display and it works perfectly with my previous MBP 13 intel model via official Apple Digital AV Multiport connected by HDMI cable. After I upgrade my laptop to MBP 14 M1 Pro this summer my monitor was struggling with all symptoms mentioned right there. Flickering, screen retention after open background with deep black color, all of this problems make work with my display unacceptable. I read different thread about this problem, something like switch RGB profile, disable true tone and etc. Only solution which help me to stop this problem - I connect my monitor to laptop via USB-C to DisplayPort cable without any adapters.
When I connect monitor via HDMI - HDMI output colors was ypbpr. Now via USB-C -DisplayPort it is rgb. Maybe problem was there?
Hope my info will help someone, good luck.

 

[JVXEVCWMUJGOHIKQ]

Hi. I've been struggling with this issue for quite long and found many opinions that this occurrs randomly. In my case there are several pages that have almost 100% chance to cause flicker/retention. I attach a full resolution screenshot as an example. Seems that this color + multiple vertical lines are more likely to force this issue. I'm currently using BenQ PD3220U. If you have the same problem and Apple says they are not able to reproduce it, send them this.

I have two Dell monitors connected to an M1 Macbook Pro 14. Dell S2722QC and Dell S2721QS. The QC is connected by a USB c (thunderbolt) cable that came with the monitor and the QS is connected by hdmi to hdmi.

As mentioned in the comment I'm quoting, it happens to me also in a specific similar scenario when writing code in visual studio code and there are tons of small characters on screen using a dark theme.

It's pretty insane that this is actually a thing but I'm glad people have confirmed it to be real. Not on Ventura yet as it's a work laptop and we don't have the update so far.

 

[nitestryker]

just went out and bought an apple tb3 cable, and it seems to have temporarily fixed the problem

 

[genexx]

@nitestryker
thumbs up for the cable, as Macs are special with them.

My Dell S2722DC works fine although supposedly not. Just turn off the DDC/CI on the monitor and set a fixed frequency, then nothing flickers.

There is a problem with the variable refresh rate which does not occur with all monitors and often when connected via HDMI.

It is best to set a fixed refresh rate in case of problems and disable DDC/CI or G-Sync or Freesync on some monitors if possible.

 

[ferjilo]

just went out and bought an apple tb3 cable, and it seems to have temporarily fixed the problem

Hi, is still working fine? Ive been flicker-free for many weeks (adjusting screen settings) but its slowly coming back…

 

[Finerdly]

I'm horrified to say the flicker came back for me after months of no issue at all.

I had it solved perfectly for months with automated switching from VRR to fixed refresh rate. It's still switching, but now the fixed refresh rate doesn't seem to solve the issue anymore - which it did 100% of the time before..

Anyone else also experiencing this despite using fixed refresh rate?

EDIT: Watching youtube videos seems to be the perfect trigger for the issue.. then it gets really noticeable to the point of being unusable. I watched a lot of youtube in the last months and the issue never re-occured, but now it's back..

 

[Tek5]

I'm horrified to say the flicker came back for me after months of no issue at all.

I had it solved perfectly for months with automated switching from VRR to fixed refresh rate. It's still switching, but now the fixed refresh rate doesn't seem to solve the issue anymore - which it did 100% of the time before..

Anyone else also experiencing this despite using fixed refresh rate?

EDIT: Watching youtube videos seems to be the perfect trigger for the issue.. then it gets really noticeable to the point of being unusable. I watched a lot of youtube in the last months and the issue never re-occured, but now it's back..

To add to this: something similar happened to me.
Well, it was never completely gone as in your case, but it was much better than at the start (what I did was to try out different color profiles in System Settings -> Displays).

A few days ago I checked the Displays settings again and noticed that with Ventura you can now also set the Refresh rate (although it's possible that this option existed also in earlier versions, however I never noticed it). I thought that setting the refresh rate to the one configured in my display may resolve all the remaining issues, so I gave it a try and I couldn‘t have been more wrong. Now I‘m basically back to square one, when the problem first started, meaning, that it happens much more frequent than the last few months.
Even changing all the settings back to the ones that improved the situation, didn't do much. It‘s just very very strange and yeah, annoying.

 

[Finerdly]

To add to this: something similar happened to me.
Well, it was never completely gone as in your case, but it was much better than at the start (what I did was to try out different color profiles in System Settings -> Displays).

A few days ago I checked the Displays settings again and noticed that with Ventura you can now also set the Refresh rate (although it's possible that this option existed also in earlier versions, however I never noticed it). I thought that setting the refresh rate to the one configured in my display may resolve all the remaining issues, so I gave it a try and I couldn‘t have been more wrong. Now I‘m basically back to square one, when the problem first started, meaning, that it happens much more frequent than the last few months.
Even changing all the settings back to the ones that improved the situation, didn't do much. It‘s just very very strange and yeah, annoying.

So the upgrade to Ventura didn't change the situation at first? Or how long were you using Ventura before changing Display settings? I didn't upgrade yet to wait if some issues like you're describing now will show up

 

[Tek5]

So the upgrade to Ventura didn't change the situation at first? Or how long were you using Ventura before changing Display settings? I didn't upgrade yet to wait if some issues like you're describing now will show up

Installed the Ventura update roughly a month ago and changed the settings around last week, so no, Ventura update wasn't the cause (unfortunately it also didn't solve the problem in the first place).

 

[oz_rkie]

As I've mentioned a few times in this thread, all these so called fixes/workarounds are at best temporary and at worst just placebo effects. I was convinced that the m1 (and even m2) have hardware level incompatibilities and severe issues with a non trivial number of external monitors. No amount of settings changes etc will fix it imo.

The monitor's I've been using for a long time before I bought the m1 macs were working flawlessly, and now that I've sold off my macs after becoming tired of this annoying issues, guess what, the same monitors are back to working flawlessly with my non apple computers.

 

[matteomonizza]

Same problem here with two BENQ PD2720U.. Tried everything, nothing works.. I've tried to ask to apple's support..

 

[Spacegray]

...but they heard about this problem for the first time - right?

 

[matteomonizza]

...but they heard about this problem for the first time - right?

No answer by now... Hei MacRumors, can't you help us?

 

[matteomonizza]

Today I cannot work, monitor is going crazy in flickering.. Cant believe that this issue is not known by Apple..

 

[matteomonizza]

Today I accidentally found the cause of the problem. Lighting a lamp in my office, after a minute, the problem started to appear. I linked this to the True Tone feature. I then tried to turn it off and slowly the monitor stops flickering and ghosting, turning the True Tone back on the problem comes back.

 

[zarino]

Today I accidentally found the cause of the problem. Lighting a lamp in my office, after a minute, the problem started to appear. I linked this to the True Tone feature. I then tried to turn it off and slowly the monitor stops flickering and ghosting, turning the True Tone back on the problem comes back.

@matteomonizza it’s good to hear you’ve resolved your issue. But if it was indeed caused by your Mac’s True Tone sensor, then it’s not the same issue other people in this thread have been experiencing, as there are examples further up this thread of this flickering/ghosting/pinstriping issue happening on Macs without a True Tone sensor, such as the Mac Studio and M1 Mac Mini.

 

[matteomonizza]

@matteomonizza it’s good to hear you’ve resolved your issue. But if it was indeed caused by your Mac’s True Tone sensor, then it’s not the same issue other people in this thread have been experiencing, as there are examples further up this thread of this flickering/ghosting/pinstriping issue happening on Macs without a True Tone sensor, such as the Mac Studio and M1 Mac Mini.

You are right! My issue result is the same as I've seen in photos and videos in this thread. But of course, on a Mac Studio, is not possible. Maybe disabling true tone feature can help some one..

 

[jdrch]

View attachment 1683286

This is the exact same problem I'm having on a ViewSonic VP2768-4K connected to a Mac Mini A2348 via Monoprice certified Ultra High Speed HDMI cable (HDMI to HDMI). That display is also fed by a Windows 10 Dell XPS 8500 Special Edition with an AMD Radeon HD 7870 GHz Edition via mDP out to DP in.

Everything was working just fine until the Mac Mini's background changed while Night Shift was enabled. At first I got horrible ghosting on the Mac Mini's input only, then flickering on both the Mac Mini HDMI and Dell XPS DP inputs. Turning off Night Shift on the Mac reduced the flicker on its input while turning off Night Light on the Dell eliminates it entirely on that input.

My guess is the Mini detects the ultra high speed HDMI cable, assumes the display can support HDR, and so sends it a signal it can only partially read/understand. I have seen similar effects occasionally with my Xbox Series X and TCL 55R625.

No firmware update available for the display, so not sure what else to do. In the meantime the flickering has mostly stopped since I posted this, but I expect it to return.

 

[ChrisMichael]

Since my first post on Nov. 1st, I tried a few more things with my Asus VP28U and Mac Mini M1:
-Removing cables like ethernet, USB, headphones, carefully rattling the USB-C to Display port cable a bit, while the vertical lines showed up... which did nothing.
-I made a calibrated color profile for my monitor with the rather unknown but very useful app Gamma Control 6.
-Tried all kinds of settings and combination of settings, power cycling etc., I mentioned in my post on Nov. 1st once again.

The cable I use since July 2022 is: Stouchi USB C DisplayPort 1.4 8K@60Hz 4K@144Hz
Before this one, I had: uni USB C to DisplayPort-cable (4K@60Hz, 2K@165Hz), 1m/3ft

My conclusion at this point is:
There is no permanent fix.
Everything I tried since Sept. 2021, only shifted the issue over to other apps or websites.
With my current settings and color profile it's the tiled images view (feed) of Instagram-Profiles triggering it almost for sure.

When the vertical lines appear, they may temporarily disappear, when I change some graphics settings in the Mac system preferences and they also disappear, when I only change settings in the monitors OSD.
What is this supposed to tell us?
Possibly, when the Mac goes into flickering/lines mode, depending on the displayed image, there is something wrong with the output of the Mac, that can only take effect on the monitor under certain circumstances (settings) of the monitor.

I contemplated on buying an LG Ultrafine 5K the last few weeks, but after reading through forums, there might be a good chance, this issue (or related ones) would be likely to reappear.
Buying a Mac mini and having to rely on an external display was a bad idea from the beginning, it seems.

I'm so disappointed, Apple is unable to fix this since over 2 years.
Not even the Ventura update stopped it.

 

[genexx]

@ChrisMichael

have you tried to disable

• Adaptive-Sync/FreeSync

In the Manual i can See there is a Menu Item, if you can disable, try ;-)


My Dell S2722DC is listet as Problematik, but disabling of DDC/CI in the Monitor Menu does fix it.

 

[cliffordyen]

@ChrisMichael

have you tried to disable

• Adaptive-Sync/FreeSync

In the Manual i can See there is a Menu Item, if you can disable, try ;-)


My Dell S2722DC is listet as Problematik, but disabling of DDC/CI in the Monitor Menu does fix it.

I have a similar monitor Dell S2722QC, and I can confirm disabling DDC/CI does NOT fix it even with fixed 60Hz refresh rate.

 

[ChrisMichael]

Same here, turning DDC/CI off was amongst the many things I already tried without success.
Tried it again, but it didn't lead to a different outcome.
Thank you for the tip nontheless, @genexx

Turning Night Shift on, while the lines and flickering occurs, makes them disappear and vice versa.
That is, because certain patterns and particular shades of grey or a combination of both being displayed triggers the phenomenon.
By changing the monitors color profile, i can make Instagram stop flickering and shift the issue to other websites for example.
Even the right-klick context menu can make it stop in some apps.
Activating the monitors OSD Menu will stop the flicker for sure.
It is perfectly reproduceable.
On MacRumors, for example there ist no problem at all with my current color profile.

A skilled programmer could possibly write an app that scans the displayed image for problematic patterns, then displays a "counter-pattern" somewhere as a workaround.

 

[jdrch]

Same here, turning DDC/CI off was amongst the many things I already tried without success.
Tried it again, but it didn't lead to a different outcome.
Thank you for the tip nontheless, @genexx

Turning Night Shift on, while the lines and flickering occurs, makes them disappear and vice versa.
That is, because certain patterns and particular shades of grey or a combination of both being displayed triggers the phenomenon.
By changing the monitors color profile, i can make Instagram stop flickering and shift the issue to other websites for example.
Even the right-klick context menu can make it stop in some apps.
Activating the monitors OSD Menu will stop the flicker for sure.
It is perfectly reproduceable.
On MacRumors, for example there ist no problem at all with my current color profile.

A skilled programmer could possibly write an app that scans the displayed image for problematic patterns, then displays a "counter-pattern" somewhere as a workaround.

Ha, you tried just about every suggestion I had. Thanks for being thorough.

Scanning the frame buffer would be kinda hacky. The proper fix here is probably for Apple to update the GPU driver. Given the oddities people have noticed with Intel's new dGPUs it's not entirely surprising Apple would have difficulties. The first couple forays into something as complex as a GPU are bound to have a few issues.

 

[genexx]

I have a similar monitor Dell S2722QC, and I can confirm disabling DDC/CI does NOT fix it even with fixed 60Hz refresh rate.

Maybe i am Lucky ? Do you have connected the Monitor via HDMI ? Mine is connected via USB-C and charging the MBA M2 same time with no problem. 75HZ 2K
The HDMI Port is known to be "problematik" on Mac, even on Hackintosh ( I5-10400 UHD630 ) it was best to connect via DP or USB-C wich is basically DP.

On Macbook some users where successful with disabling True Tone and Automatic Brightness if and when Internal Display is used ( makes no difference in my case )

@cliffordyen

this is what helped, another Dell S2722QC User reported:

S2722QC, MacBook Pro M1 Pro, settings for usage​

Dell S2722QC
Things to do for trouble free operation [clear text, no flickering, no problems waking up from sleep]:

1. Update to the latest macOS.
2. To get 4K/60Hz with USB-C:
   1. Go into the monitor’s OSD. [All settings should be at Factory Defaults.]
   2. “Display” -> “USB-C Prioritization”
   3. Change to “High Resolution”. [This setting increases the bandwidth used for video at the cost of reducing USB data speeds.]
   4. “Display” -> “Smart HDR”
   5. Make sure it’s set to “Off”. [When it’s set to on, the refresh rate on your monitor will fluctuate and be variable.]

To verify, go into your MacBook’s display settings and check the resolution and refresh rate. The resolution for the Dell should be “Default for Display” and the refresh rate is “60 Hertz”.
You’ll also want to turn off “True Tone” under the built-in display settings. For some reason it applies to both displays instead of just the laptop’s.
Good luck!

 

[cliffordyen]

Maybe i am Lucky ? Do you have connected the Monitor via HDMI ? Mine is connected via USB-C and charging the MBA M2 same time with no problem. 75HZ 2K
The HDMI Port is known to be "problematik" on Mac, even on Hackintosh ( I5-10400 UHD630 ) it was best to connect via DP or USB-C wich is basically DP.

On Macbook some users where successful with disabling True Tone and Automatic Brightness if and when Internal Display is used ( makes no difference in my case )

@cliffordyen

this is what helped, another Dell S2722QC User reported:

S2722QC, MacBook Pro M1 Pro, settings for usage​

Dell S2722QC
Things to do for trouble free operation [clear text, no flickering, no problems waking up from sleep]:

1. Update to the latest macOS.
2. To get 4K/60Hz with USB-C:
   1. Go into the monitor’s OSD. [All settings should be at Factory Defaults.]
   2. “Display” -> “USB-C Prioritization”
   3. Change to “High Resolution”. [This setting increases the bandwidth used for video at the cost of reducing USB data speeds.]
   4. “Display” -> “Smart HDR”
   5. Make sure it’s set to “Off”. [When it’s set to on, the refresh rate on your monitor will fluctuate and be variable.]

To verify, go into your MacBook’s display settings and check the resolution and refresh rate. The resolution for the Dell should be “Default for Display” and the refresh rate is “60 Hertz”.
You’ll also want to turn off “True Tone” under the built-in display settings. For some reason it applies to both displays instead of just the laptop’s.
Good luck!

I use the USB-C cable came with the monitor connected my MacBook Ari M1 directly to the monitor, and yes, I tried all the things you can think about, including the one you posted. What I didn't realize when I replied to your comment is that S2722DC is 75Hz 2K, while S2722QC is 60Hz 4K. Maybe that's the reason that makes them different.

Nevertheless, thanks for reporting your experience.