LG Ultrafine 5K M1 Mac spurious vertical shift in a 2 inch band on screen

Do you still seriously consider up to now that the screen is the problem? Look, we have these sorts of problem with mac mini M1 with multiple brands and models reported already. Even on AASP's service monitors/displays, they were able to replicate the problems/issues we reported.

Replacing the screen with a "working" model does not solve/fix the issue with mac mini M1. It just masks the problem! A perfectly working screen with other devices (Windows 10, intel-based PCs, intel-based mac mini, intel-based laptops) is not the problem. IT.IS.THE.MAC.MINI.M1!

Definitely a mac mini M1 issue. Before bringing to the AASP, I tested my unit with other displays (which are perfectly working with intel-based PCs and macs) I have here at home using VGAs, HDMIs, USB-C to HDMI adapters and cables--same problem appears.

Called Apple Care tech support to report the issue and I was referred to one of the AASPs. AASP techs could not figure out what's wrong with the mini M1 as all diagnostics return a "Pass" mark--but they could see the problem with their own service displays. MLB has been replaced, and that out-of-the-box MLB showed the same display issue. Senior tech advisor said that it is possible that the replacement MLB is also defective. What? haha. Talked to the senior tech advisor and confirmed with him that there is no official acknowledgement/recognition yet from Apple regarding these external display issues--no internal memo, no revised service guide yet to deal with these. All the senior advisors I talked to could offer is for me to try swapping cables, using "Apple-certified" cables and displays, use "Apple-certified" display adapters, etc. There's nothing else they could offer: 7/7 senior tech advisors. My unit is with the AASPs for 60 days already. Waiting for another replacement MLB. AASP already uploaded/sent to Apple tech 2 service reports already describing the issue.

LG screen manager update for mac M1

Its specifically related to the thunderbolt 3 cable spec. As other users have said, replacing it with another Thunderbolt cable won't resolve it.

Use the USB-C cable (the other one) that came with it. It should work just fine.

Me too, me too! I got the monitor fro BestBuy in January 2021 to go with a 16in MBP I got in December.

I've seen the stripe be different widths and occurring at different offsets (left or right). Of course I notice

it most when it's in the middle of the screen.

I can verify that the problem is not coming from the Mac (screen-shot does not show it);

I have to photograph it to demonstrate the problem. I'm using the cable that came with the monitor.

This started a couple of months after I got the monitor, and I was very disappointed. Then in the mid-summer,

believe it or not, a tiny little and climbed in just behind the glass and got stuck about 40% to the right

and 50% down, right in the middle of where I look.

I was not disappointed when (Nov) I came in to work and the monitor went orange and purple during a Zoom

meeting (of course). The display broke in some way. Fortunately it was still under the 1-year warranty. I spent a

some time on the phone with LG who sent me a shipping label and I sent it in for repair. I just got it back

(couple of weeks ago) and the ant was gone! Whatever they did, they fixed the monitor.

But yesterday, I saw the stripe of offset pixels again.

I typically carry the laptop in to work, open the lid so it wakes up and understands that it is not connected to anything,

then plug in the USB-C cable (which is carrying power+monitor) and let it figure out that there are 2 monitors.

Next time I'm down there I'll try unplugging it from the wall and see if that makes the stripe go away.

I also have a 4K monitor from LG and I have not seen that problem.

Jules

Disabling the Energy Saver option to prevent computer sleeping did not help, the issue still occurred sporadically after waking up the sleeping monitor in Big Sur 11.2, so I'm going back to the USB-C cable which has so far proven to be the only way to completely avoid the problem. I'll keep trying again after later OS updates arrive to see if anything changes.

it will not get fixed as I stated in my earlier comments. LG no longer manufactures this monitor and has zero interest in addressing the issue that effects a tiny portion of the market. Apple doesn't care for the same reason. Plus they want us to buy the new iMacs and their own consumer level priced monitors that are in the works. Just live with it. Use hot corners to put the monitor to sleep and wake up to get rid of the distortion when it happens.

I am using LG Ultrafine 5K with MacBool Pro 13 "and I have the same problem. Experimenting with different Thunderbolt cables I noticed that the problem depends on the length of the TB cable (also possibly due to the quality of the cable). When I use 2 m cable that came with the display, the problem appears more often, and the time to wake up the MacBook using the Bluetooth keyboard is much longer than using the shorter TB cable.

To solve this problem, I use a hot corner to put my Mac to sleep and wake it up.

Yes...I have the same issue...it is a one inch wide vertical shift...sometimes it is there and sometimes it is not. I also have a new M1 mini. My monitor is in the 30 day return window. I am going to return and swap out for the exact same model.

I am thinking it is the monitor. If the defect occurs in the 2nd monitor I am sure it is the M1 Mini....

Maybe the cable switch is the answer. The problem is random.

Just use the USB-C cable instead of the Thunderbolt-3 cable that came with the monitor. :)

Do you get the full 5K resolution with when the USB-C cable connection or does it drop to 4K?

for information I have reset my 27MD5KL-B with the application LG !

I'm waiting to know if the bug will recur

Hello @Louis2057: Try to sleep and wake the display multiple times in a row ( at least 20 times) and check if the pixel shift occurs.

you have to do a clean installation and if possible with configurator 2 in DFU mode !

https://youtu.be/zM6I5b1uZPE 

Hi Ross, thanks for the info.

I have an Apple M1 Mac mini and a new (as of December 2020) LG UltraFine 5K monitor (27MD5KL-B). Evidently the cable that came with the monitor is Thunderbolt. When I look at the System Information app's Hardware > Thunderbolt, I see that my monitor is connected on Thunderbolt Bus 0.

For what it's worth (probably nothing), when I look at Hardware > USB, the display's camera and audio are ultimately on the USB 3.1 bus. The display is not.

If I have time today, I'll go out and get a USB-C cable to see if that changes my luck.