M1 Mac Mini - Pixel issue on Apple Thunderbolt Display 27"

[ViRGES]

Hi there,

I was just wondering if anyone has any ideas what's going on with my M1 Mac mini. I have the following pixel shifting at the top of my display

(See Attached)

This isn't visible though on my other monitors / tv.

Your probably thinking well it's the thunderbolt then. Well I connected my two other MacBooks to this exact display and they don't have the weird pixels either!

Any advice would be welcome my friends!

Thanks

 

[xraydoc]

Hi there,

I was just wondering if anyone has any ideas what's going on with my M1 Mac mini. I have the following pixel shifting at the top of my display

(See Attached)

This isn't visible though on my other monitors / tv.

Your probably thinking well it's the thunderbolt then. Well I connected my two other MacBooks to this exact display and they don't have the weird pixels either!

Any advice would be welcome my friends!

Thanks

Try a different Thunderbolt cable. You can actually plug the laptop into the empty TB port on the back of the display and it will work. Internally, the attached Thunderbolt cable and the Thunderbolt port on the back of the display are interchangeable.

If you're using Apple's TB2-TB3 adapter, see if you can borrow another one and try that. Even though you say it works on your other machines, perhaps your new mini is more picky.

 

[ViRGES]

Try a different Thunderbolt cable. You can actually plug the laptop into the empty TB port on the back of the display and it will work. Internally, the attached Thunderbolt cable and the Thunderbolt port on the back of the display are interchangeable.

If you're using Apple's TB2-TB3 adapter, see if you can borrow another one and try that. Even though you say it works on your other machines, perhaps your new mini is more picky.

The weird thing is everything was fine until recently. It's what kind of makes me think an update has done this or my Mini is faulty!

 

[uller6]

Try a different Thunderbolt cable. You can actually plug the laptop into the empty TB port on the back of the display and it will work. Internally, the attached Thunderbolt cable and the Thunderbolt port on the back of the display are interchangeable.

If you're using Apple's TB2-TB3 adapter, see if you can borrow another one and try that. Even though you say it works on your other machines, perhaps your new mini is more picky.

Really? I had no idea the built-in cables/TB ports were interchangeable on these!

 

[xraydoc]

The weird thing is everything was fine until recently. It's what kind of makes me think an update has done this or my Mini is faulty!

Strange that it would only be that specific combination and not on all other monitors connected to the mini.

 

[ViRGES]

Strange that it would only be that specific combination and not on all other monitors connected to the mini.

Exactly haha! What I really need is another M1 to test on this monitor, that would answer my question.

 

[Coheebuzz]

Same here, see this thread... https://discussions.apple.com/thread/252337692

Happens on both of my Thunderbolt and LED Cinema displays and it's like 100 pixels long on the latter.

Let's see if 10.3 does anything as it supposedly fixes display issues for some.

 

[jdb8167]

The built-in cable on Thunderbolt displays have a tendency to corrode over time. These monitors are pretty old. You can buy a replacement and a kit to disassemble the monitor but as mentioned above, the easiest solution is to just use a normal Thunderbolt 2 cable in the extra port. Works fine.

My TB Monitor was causing weird problems including random lockup’s and kernel panics until I used a new TB2 cable. Mine is from 2011.

 

[Coheebuzz]

I've already tried them on my MacPro, on my iMac and on my wife's laptop and the glitch isn't there, this is specific to the Mini M1 it seems. I've also spoken with the monitor technician at my local store who said that misalignment glitches like these are typically monitor firmware or driver problems. We reported it, let's hope Apple is motivated enough to have a look at it.

 

[xraydoc]

I figured I'd share an update.
I connected my TB Display to my MacBook Air M1 this morning. I see the same small pixel glitch that the OP has in his pictures.
Must be something specific to the M1. I've not tried a different TB cable yet.

 

[TheRes0rector36]

same here iv had my Mac mini for almost 2 months at first I thought I bought a broken used Thunderbolt Display even though I tested it out before I bought it. its pretty annoying hopefully there's a fix soon

 

[Significant1]

I have the same problem, when using my late 2009 iMac as monitor. Thought it was because my usb hub was poor. That is displayport via usb hub, No thunderbolt.

The same mini displayport cable Works without artifacts, when connecting my old 2014 air to my iMac.

 

[timidpimpin]

They call it the bleeding edge for a reason. You chose to be there.

 

[xraydoc]

I have a Thunderbolt 4 multi port hub on its way. I’ll retest the Thunderbolt Display when it arrives.

 

[Significant1]

I have just discovered, that only fullscreen spaces have the problem. No problem with at desktop space, even if I hide menu-bar select and select black background color to make the glitch more visible. Smells like driver/software issue to me ?

 

[Coheebuzz]

To make the glitch more visible you can try a wallpaper which has different tones for the top and bottom, i.e. that changing sky wallpaper, it won't be visible with a solid background because it would be duplicating pixels of the same color.

 

[Coheebuzz]

Here's a quick video of it, as you can see it's not visible when the wallpaper is flat but it can get pretty distracting otherwise.

 

[xraydoc]

Here's a quick video of it, as you can see it's not visible when the wallpaper is flat but it can get pretty distracting otherwise.

View attachment 1750125

The artifact on mine is like the smaller of the two examples here.

 

[Zeebedy]

When I changed my monitor, I had artefacts and on screen, with the mini HDMI port, but before that port and cable were working fine, I think it was to do with the 1440p resolution that was trying to run..

So I bought a USB4 to Display Port cable, and now running sweet at 1440p 120hz!

 

[Coheebuzz]

The artifact on mine is like the smaller of the two examples here.

I'll trade you with the mothership of the Unidentified Flickering Pixels!

 

[Significant1]

To make the glitch more visible you can try a wallpaper which has different tones for the top and bottom, i.e. that changing sky wallpaper, it won't be visible with a solid background because it would be duplicating pixels of the same color.

Yeah, I did some testing and you are right. I depend on what is shown on the screen. It is like som color registers. Even with a black background it starts to appear, when windows are shown. Anyway, I don't think it is neither thunderbolt (as I see it on a non-thunderbolt usb-hub) or cable issue (same cable show no issues on my old machine). I think it is either a hub-chipset or m1 display driver issue. Unfortunately, I don't have a direct usb-c to mini displayport cable I could try, so I could eliminate my hub from the equation end isolate the problem further.

 

[xraydoc]

Yeah, I did some testing and you are right. I depend on what is shown on the screen. It is like som color registers. Even with a black background it starts to appear, when windows are shown. Anyway, I don't think it is neither thunderbolt (as I see it on a non-thunderbolt usb-hub) or cable issue (same cable show no issues on my old machine). I think it is either a hub-chipset or m1 display driver issue. Unfortunately, I don't have a direct usb-c to mini displayport cable I could try, so I could eliminate my hub from the equation end isolate the problem further.

I think it's pretty well isolated to a phenomenon between the M1 and this particular monitor whether hub are part of the equation or not. I'm plugging mine directly into one of the ports on the machine (via Apple's TB2-TB3 adapter) and have the same artifact as others who use TB hubs. It also seems to be specific to this monitor as other Thunderbolt monitors, particularly the LG Ultrafine 5K, don't seem to show the same artifact. And there's been no similar artifact on any other monitor I've connected to my MBA (an LG 4K, a Dell 4K, an Asus 1440p ultrawide and a Dell 1440p).

 

[SmileyDude]

Same issue here. I have my TB display connected through an Apple TB2->TB3 adapter, connected into a Caldigit TB3+ dock. I've seen it on two machines -- an 13" M1 MBP and a M1 Mac mini. My 2018 15" MBP for work does not show an issue with the exact same connection. I've seen this on every version of macOS so far on my M1 MBP since I got it back in November.

I also have an HP 27" 1440p display that I've used with my MBP and I do not have the issue there. There is definitely something particular to the TB Display and the M1.

 

[uller6]

I have this exact same problem using my 2008 24" LED Cinema Display with my M1 iMac through a generic USB-C to mini DisplayPort adapter. I've been using the display with a 2012 Mac mini without issue for a long time but only recently moved it to the M1 iMac and noticed the problems.

 

[AGANG]

Unfortunately, same issue here...
I have an apple thunderbolt display 27". Until now I have used it with a macbook pro retina 2015 13" through thunderbolt 2 cable and it worked perfectly fine.
I have purchased a new M1 Macbook pro and I'm using my monitor with an original apple thunderbolt 3 to thunderbolt 2 adapter. I have noticed a small amount of pixels close to the right corner of the display, which are flashing as a vertical music soundbar, but when I switch between windows vertically, at some pint I cant see these moving pixels.
Do you have any idea, what is it? Adapter problem? Bis Sur OS problem?