The second monitor in my dual monitor setup (2 LG UltraFine 4k's) is flickering, and this only started a few days after downloading Sonoma. Both monitors are individually plugged into a M2 Mac mini. I'm not daisy chaining here. No changes to power supply. Is anyone else experiencing the same issue?
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Dual monitor flickering on macOS Sonoma
- Thread starter pcd213
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I was doing a lot of A/B testing to figure out what could be wrong. For now it appears that a 6 way outlet adapter from Ikea that the Mac mini was plugged into may have been causing the flickering on the 2nd monitor. I'm in a bit of disbelief because the monitor, itself, was not plugged into this outlet adapter - it was plugged into a separate outlet due to location. So I have my fingers crossed that me eliminating the outlet adapter (which I didn't really need) will solve the issue. If so, sorry for being so quick to judge you, Sonoma!
I've got the same monitor and it's plugged directly into my M1 MacBook Pro. Only the LG will flicker at random times. It's definitely got to be a bug in the OS?
I'm sad to report that the issue is back this morning. I may post this on a different section of Mac Rumors, as well. Here are some interesting details that I have noticed.
(1) When the flickering happens on the 2nd screen, the open window/program on the first screen sort of quickly zoom in and out.
(2) As the flickering happens on the 2nd screen, and I have a window in my first screen that I'm typing on (as I'm doing right now), the text that I'm typing will have a visible delay in appearing on the first screen even though the first screen remains lit.
(3) When I have the Displays setting window opened on the 1st screen, and the flickering happens on the 2nd screen, I always see both monitors appearing in the Display settings. The second monitor doesn't disappear from the settings pane when it flickers.
(4) I have a Magsafe charger plugged into the 2nd screen with AirPods Pro sitting on it, and when the second screen flickers, I do not see the AirPods Pro stoping and starting charging.
(5) The issue appears to happen more frequently as I'm typing or scrolling or doing something on the computer.
Here's a video of what's happening:
https://share.icloud.com/photos/0f9EZMVfnGXjSghhDeWi2JhYw
Setup:
- Two LG Ultrafine 4k monitors (24MD4KL)
- 2023 Mac mini M2, 8gb
(1) When the flickering happens on the 2nd screen, the open window/program on the first screen sort of quickly zoom in and out.
(2) As the flickering happens on the 2nd screen, and I have a window in my first screen that I'm typing on (as I'm doing right now), the text that I'm typing will have a visible delay in appearing on the first screen even though the first screen remains lit.
(3) When I have the Displays setting window opened on the 1st screen, and the flickering happens on the 2nd screen, I always see both monitors appearing in the Display settings. The second monitor doesn't disappear from the settings pane when it flickers.
(4) I have a Magsafe charger plugged into the 2nd screen with AirPods Pro sitting on it, and when the second screen flickers, I do not see the AirPods Pro stoping and starting charging.
(5) The issue appears to happen more frequently as I'm typing or scrolling or doing something on the computer.
Here's a video of what's happening:
https://share.icloud.com/photos/0f9EZMVfnGXjSghhDeWi2JhYw
Setup:
- Two LG Ultrafine 4k monitors (24MD4KL)
- 2023 Mac mini M2, 8gb
That's interesting.. Mine kinda flickers a bright white for a split second. I can't see any rhyme or reason why it happens though. I do work remote and remote into my work computer, I don't know if that software does anything or not. I'll try to use my computer more this weekend and see if it happens when RemotePC isn't running.
I'm doing a lot of A/B testing to see what's happening. I just tried to only have the 2nd monitor plugged in, removing the thunderbolt cable from the second monitor. After a few minutes I noticed the second monitor went to black and then came back on. I'm going to run the same test for the first monitor to see what happens. If the first monitor runs flawlessly I may try to replace the thunderbolt cable to test that. If that doesn't work, dare I say it, maybe it's a display problem. That would be so, so upsetting.
Duplicate color profiles.
On 2023-10-17, after upgrading to Sonoma on Mac mini with M1 chip, I, too, had screen flickering. I found another user had the same problem and resolved it by deleting the duplicate files in ~/Library/ColorSync/Profiles/.
I did this too, and the problem ceased. [See this link:](https://discussions.apple.com/thread/254863490?answerId=259057938022#259057938022/)
On 2023-10-17, after upgrading to Sonoma on Mac mini with M1 chip, I, too, had screen flickering. I found another user had the same problem and resolved it by deleting the duplicate files in ~/Library/ColorSync/Profiles/.
I did this too, and the problem ceased. [See this link:](https://discussions.apple.com/thread/254863490?answerId=259057938022#259057938022/)
I believe the incident is related to changes in Sonoma, since it was working before upgrading.
Should you move the thread back to the Sonoma thread?
Should you move the thread back to the Sonoma thread?
Thank you for the tip.
For me, with a WAVLink docking station, the problem was not the profile but the "frame rate".
My monitors only support till 144 but Sonoma configured it by default at 256
After changing it, no more flickering
The strange thing was that it only happened for one of the two monitors, the other was working fine.
I have a repeatable flickering problem with my Mac Studio and Sonoma 14.4. Every time I do anything with my Audio profiles, like switching between audio devices, AirPod's, Homepods, my wired FiiO K7, YouTube flickers sometimes to a extended black screen. All cables checked no problem. It did not do this before the upgrade. As long as a don't touch these settings everything is fine.
I have found the reason for the flickering display and the strange behavior of the "Sound" tab. A bad HDMI port on the Yamaha AVR all my computers are connected to. The HDMI plug might be dirty. I will hit it up with some Caig DeOxit and install a new cable. I have the Mac plugged into unused HDMI port and it is working OK. no screen flickering. The installation of 14.4 was a coincidence.