Mac Mini (M1) 2020, LG UHD monitor flickers on dark colours.

This is how it looks on my Dell 3221QS and Macbook Air running Montery 12.0.1. Connected over HDMI in RGB mode (YCrCb is far worse and DisplayPort is even worse) at 3840x2160 60Hz.

https://imgur.com/a/tzYkrfS

Hi everyone,

I’ve bought a refurbished Mac Mini M1. Arrived with Monterey 12.2.1. I hooked it to my LG 27”HDR 4K monitor which has been working well for more than one year with my old intel Mac Mini under High Sierra.

Soon the monitor started flickering and turning black.

The same beaviour hooked to HDMI or Thunderbolt ports, the only options on the new Mac Mini.

Then upddated to Monterey 10.3.1, worked fine for a while and then it started to go black showing the message “no signal entrance, going to sleep after 1 minute”.

A little search and I’ve found the problem with external screens and M1 chipset is well known but no sollution announced from Apple yet.

Before to return the Mini I’ve called the Support Service, one hour on the phone with six different people included a remote diagnostic session that showed “no problems” on my system or the answer : “Sir, we have never eard about this kind of issue”, “it could be a incompatibility problem with your monitor” or simply “have you tested it with other monitors?”.

Then I decided to return the Mini to the Store.

My opinion, the Support attitude was 10 over 10, the results was zero and worst, M1 is there from 2020 as this thread but there are no sollutions known from Apple.

I have two monitors, one is USB-c-DP and other is HDMI-HDMI, the first one is also working flawlessly, but HDMI is the big pain...

This is the issue of the monitor. you better disable HDR and black stabilizer.

After I change the monitor to Benq ew3270u, it is solved.

So I've spoken to Apple support. A nice conversation, but not helpful in the end. They asked if contacted LG, told me to restart my Mac etc. They suggested that I try to connect via USB-C. After ruling out the obvious they said that they will notify people up the ladder. Apart from bugging them like this (via support) it might be useful to let them know via https://www.apple.com/feedback/macmini.html

I think I will be forced to return my monitor and try another model/brand.

I have 2x UHD LG 27" UL600 model. First I though it was the monitor then the problem went away but then it came back. I swapped the monitors around and the problem still occurs randomly. It only happens to the HDMI connection, Thunderbolt is fine and too bad the M1 won't allow you to run dual display off of the thunderbolt ports.

I tried changing resolution as well and it does not fix the issue.

I hope there's a fix soon. This makes one of my monitors completely useless at times.

for a temp fix. It seems like if I change the background image to black, it helps a bit there is less “flickering” on areas that I don’t have an open window on. I did this a few times when flicker returns and it goes away after a few tries.

last 2 days it was fine as I use the monitors for over 8 hours a day.

I also noticed that sometimes the second display does not wake up unless I disconnect and reconnect the thunderbolt cable. M1 just seems buggy all around with the graphics.

I've arranged now to return the M1 Mac mini, alongside the display issues, I have repeatedly encountered issues with the Mini failing to connect to the bluetooth (Magic) keyboard as well as occasionally dropping the connection to the (magic) trackpad. Too many issues now for me to just hope that Apple sorts this out. I have seen now in previous reports that the older Mac mini also had bluetooth issues so perhaps its a problem with the build.

Such a shame as I was really hoping this would be a great little computer..... Steve Jobs would be spinning in his grave with the lack of quality control

bw

Andrew

I have just received Mac mini M1 16G/512 SSD connecting via HDMI cable to LG 32UN650 4K monitor. I have flickering intermittently also. The screen just flickers and restored regardless if I do anything special ... Apple, please fix this. I have 10 other computers running windows and none have the issue with the display.

This seems to be an Apple problem and not a Monitor issue.

Same issue here for me with my Dell S2817Q 4K monitor.

Have tried HDMI - HDMI and USB-C to DisplayPort but issue persists.

Just got off the phone with Apple who advised I need to drive a 4 - 6 hour round trip to an authorised service provider for them to investigate and try to repair, or wait until local lockdown restrictions end before I can book an appointment at an Apple Store.

They are not able to send me a replacement until a technician has investigated and I can't send it off to be looked at because the M1 Macs are "so new". Apple shipped my Mac from China to the UK, but I can't ship it anywhere in the UK because it's "too new".

Anyways ... my response from Apple is basically "sorry, you'll just need to put up with it until a technician can authorise a replacement".

Sharpness fixed the issue on one page I know to flicker and now it flickers on another page this one: https://forums.macrumors.com/threads/m1-air-ghosting-flickering-with-external-display.2271670/

tried everything now so back it all goes...

LG 27UL550 arrived today, I have them both connected to the M1 the BenQ EL2870U on HDMI and the LG on USB to Displayport , I have also reversed the connections and have seen the Ben Q shimmer and flicker / lines while the LG 27UL550 is stable both displaying the same screen. I have also run the expert mode calibration on both monitors (hold down alt when clicking on calibration) and the 2 monitors now look very very similar VA vs IPS.

The BenQ has a bit more punch on brightness and the LG has a more natural colour to it. The BenQ was £250 (although I have seen them as low as £199 last year) and the LG 27UL550 £280 so for anyone needing to get on with it before apple finally finds a fix for the M1 as others and lwc27 have recommended above the LG 27UL550 is perfect.

The only issue that remains now is every time the Mac goes to sleep all monitor settings are forgotten, since the m1 draws hardly any power anyway I think I will just stop it sleeping until apple fixes that.

Finally found your response, I got exactly the same monitor and I replaced monitor and cable a few times, finally I know this is issue with macbook, I am okay, because I bought the monitor for my ps5, there isn't a good replacement for this monitor, since I am looking for a 32 inch curved 4k display, looks like only this monitor matches my needs, now just hope apple fix this issue.

Same issue with Mac Mini M1 going into 4k Dell P2715Q. Monitor works flawlessly with every other machine; mostly a MBP - it’s a great, reliable workhorse. With the Mini, connected via HDMI, it’s fine, it’s fine, it’s fine... and then loses it, display constantly flickering and going back. Was going to try with USB-C to DisplayPort cable until I read the comments here and thought I’d save myself the effort and cash. This is obviously a problem with all of the M1 units. To say I’m unimpressed is an understatement; personally, I would put ensuring that a computer drives a monitor reliably towards the top of the checklist before daring to release it to paying customers.

I have the issue connecting my Mac mini M1 with the LG 24MK600M monitor.

I have updated latest version of Big Sur 11.2.2

Some websites are flickering in certain colors. I then found some clips to easily test.

https://www.youtube.com/watch?v=tPdLZ9g0l28

https://www.youtube.com/watch?v=LT-oNf3A7IU

Followings are my test result:

If I connect with the new LG 24MK600M monitor using HDMI port, and then I open the clip, https://www.youtube.com/watch?v=tPdLZ9g0l28

at 0:20, the screen of the clip is a bit flickering.

Also, I open the clip, https://www.youtube.com/watch?v=LT-oNf3A7IU

at 3.08, the screen of the clip is flickering over the green color (and other).

If I connect with my old VGA monitor using the HDMI to VGA converter, then open the same clips, it works fine.

If I connect with my old TV using HDMI port, then open the same clips, it works fine.

if I connect my old Notebook (Windows 7) with the LG 24MK600M monitor using HDMI, it works fine.

I try the Calibrate of the Display settings of the Mac, it does not help.

I try to set all modes of the monitor, it does not help.

Does anyone have any solution for this? Thanks.