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Intermittent monitor blank outs on LG UltraFine 4K with Mac mini M1
- Thread starter mackiee
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When I updated to 11.0.1 I had also changed to the other available port on my M1 mac mini, had not noticed a flicker since(1 week)and thought it was due to the update. I just changed back to the original thunderbolt port I was using out of curiosity and sure enough the 2 second black flicker came back.
Seeing as others have also remedied this issue by changing to the other available port, this maybe hardware related. I hope this is fixed with an update soon.
My left Thunderbolt port causes the monitor to have these intermittent blank-outs but since I changed to the right one it has not happened. Which port is causing your problem?
My left thunderbolt port looking at the mac mini from the back has the issue. My right port no screen flicker at all.
Just want to add that this port swapping fixed my monitor issue (flickering and not waking from sleep) as well. Thanks to all who posted. Just hope this is not a hardware issue and can be fixed via update.
Yes, let us hope it's not hardware related! I will try to change port when new updates arrive and see if it has been solved. If it's still an issue I will definitely contact Apple before the warranty period ends. Then one can always refer to this thread.
My Dell U2719DC blacked out three times yesterday via USC-C on my MacMini M1 with 16GB RAM and 512GB SSD. It had run for two days without this issue. It just restores after 3-4 seconds.
This happened on the third day. My second Dell Monitor, running at the same time, on HDMI has had no such issue.
This happened on the third day. My second Dell Monitor, running at the same time, on HDMI has had no such issue.
I too have experienced this with my Mac mini and the LG 5K Ultrafine. Every few hours the screen blacks out for a few seconds, then comes back. No idea how to trouble shoot. Didn't think of trying the other thunderbolt port of the Mac. Previously I was using the left port (when looking at the back), so have switched to the right to see if it reoccurs. Might also contact Apple help to see if they have any ideas.
This APPEARS to be much better with the 11.1 RC released yesterday. I have not had a blackout since I installed it.
Fingers crossed.
Fingers crossed.
M1 MBA with a 3440x1440 ultra-wide connected via a Belkin HDMI + charging adapter and kept getting 1-2 second of no signal when connected to the left port. I couldn't quite determine how/when it was happening but I haven't had a single dropout since moving to the right port.
Ditto here. Just installed 11.1 today and so far, so good!
Anecdotally, performance seems much improved on 11.1 as well. I was fairly disappointed in 11.0 with slowdowns and beachballs compared to all the raving reviews I read. Almost all of that has gone away with 11.1. Between that and this Ultrafine monitor issue, I was seriously considering returning, but no longer.
Edit: Ok, spoke too soon. Just had an instance of the monitor not coming back on again (on the left port).
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No more blackouts for me. 11.1 RC and also connected my monitor to the thunderbolt port on the right side when viewing the mini from the back.
That is probably because you are using the right-most port. It seems like it's the left port that people have problem with. You should try to change to that one and see if you still are fine.
Well I have had no more (knock on wood), even though I've been on the MacMini quite a bit.
That is not to say there has been a miracle. I have no idea what triggers the blackouts on my right hand USB-C monitor vs. my left hand HDMI right hand monitor.
I understand a BigSur update is coming soon. Maybe that will help with all the little bugs that have been happening.
I had a lot anxiety about the reported bugs before the MacMini was delivered. Now I'd say give it a chance, and if there is something you can't live with, even with potential fixes, I'd say send it back.
Any "port in a storm"
This kind of bugs me that both ports don't handle monitors well. I'll be pulling all the cables today to add an OWC Thunderbolt 11 Port dock. I'll check out what port I'm using then and flip them per your advice. I don't plan to use the OWC dock for the monitor connection, but I suppose I could use that as plan "B", though I guessing the dock would just reproduce the issue with the MacMini's USB-C port. A "Hail Mary" alternative so to speakAs my Dell still blacks out even under 11.1. I'm glad 11.1 has worked out for you BBman!
Please follow-up if the issue returns.
I have done the same, updated to 11.1 and switched back to the left port and have not seen any problems so far!
I am getting intermittent screen black outs on my LG 27UK850-W monitor. It is happening around 1-2 times per day where the monitor goes black for about 3 seconds before resuming like normal. I am running the latest version of Big Sur. I am connected via usb-c to usb-c and have tried using both ports but the issue exists on both. Sometimes the audio will no longer be working through the monitor after this happens and I am forced to restart the mac mini to get it to work again. I have not tried connecting through HDMI because I would like to save that port to use with a different device. I'm using the cable that came with the LG monitor but am considering buying an Apple usb-c to usb-c cable to see if that fixes the issue. I thought I'd ask here first to see if anyone has any suggestions. Thanks.
The same thing happens on my 27” Dell monitor via USB-C. It also happens if I use a dock.
The same monitor and cable worked fine being driven by an iPad Pro.
Clearly this is an Apple caused issue.
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Internaut
macrumors 65816
I’ve had this (very rarely) with my Dell Monitor connected DP to USB-C (both with the corporate Dell laptop and the M1 MacBook Air). I’ve never had a problem where the monitor is connected directly to the Mini DP port (2015 MacBook Pro and 2015 Thinkpad Carbon).
My current setup for both M1 MacBook Air and the corporate Dell is Monitor HDMI to USB-C hub to laptop. No issues observed so far.
My current setup for both M1 MacBook Air and the corporate Dell is Monitor HDMI to USB-C hub to laptop. No issues observed so far.
New M1 Mac mini (base config) here. I'm having something similar but only at a higher scaled resolution. My Dell S2817Q monitor scaled at 1920x1080 works fine so far but when I have the scaling set to 2650x1440 I get this occasional flickering. I'm using a USB-C to DisplayPort cable but it happened with HDMI as well (at 60Hz).
Could it be the Mini itself, Big Sur or my monitor going bad?
Could it be the Mini itself, Big Sur or my monitor going bad?