Big Sur 11.1 External Display Issues!

This morning I noted in an earlier post that two of the three worked normally. All were shut down overnight. I just noticed on the third one that the "prevent computer from sleeping automatically when display is off" checkbox was not checked.

In 11.01 We were having daily crashes with Kernal panic on M1 Air and M1 Mac Mini

https://discussions.apple.com/thread/252098649

All three have that box now checked, rebooted and now working again. I don't know if it is the fix, if if works for you please post and hopefully Apple will keep working on it.

I filed a complaint initially through Apple Support (my MacBook is covered under AppleCare still) and today through https://www.apple.com/feedback/macos.html

I have the MBP 16" and two BENQ EW3270U 4K displays. Formerly using USB-C cables with no issues under Catalina. With Big Sur I've been playing the "have you shut it off and on again" until at least one of the displays comes up in 4K HDR mode. The problem is I want both displays in 4K HDR and if one changes mode, they all change mode, and we're back to square one. My particular monitor doesn't support changing the DP version that I can tell (I think it uses DPv1.2 anyway), and HDMI doesn't support the full 10-bit YCbCr4:4:4 mode at 60Hz.

As a caveat, it works perfectly, every time, when I boot into Windows 10 Bootcamp, full 4K HDR on both displays with the same cables, no fiddling required. Makes be want to just uninstall macOS altogetherwith and maybe kick Linux around...

As for me, there is still only one solution. I am using this old (but still functional) app from App Store that enables me to work with 4K (2560x1440 @ 60 Hz). MBP 16", BenQ SW271, USB-C to USB-C cable. Sometimes after rebooting the cable needs to be unplugged and plugged again and the monitor goes blank and wakes up. But it works!

Shame on you Apple! Proffesional lives matter! We are real people not the fancy-pants designers from your ADs.

https://apps.apple.com/cz/app/display-menu/id549083868?l=cs&mt=12

I'll complain to both:

https://www.apple.com/feedback/ and

https://www.apple.com/feedback/macos.html

The more people who complain about this awful situation the better. Apple doesn't take this issue seriously because such a small percentage of its customer base have complained.

Wait for apple to fix it. No other actual solution!

in the meantime contact apple for support in order to Let them to know how many people are experiencing this issue. Also leave a feedback in here https://www.apple.com/feedback/

If we want the problem to be taken seriously, there must be a lot of us putting the maximum pressure on Apple.  So there are at least two things to do:

1- Contact customer support

2- Report the bug: https://www.apple.com/feedback/macos.html

Please, everybody, do both: call and write!

After Update - 11.2.1 - no changes - just went back to 30Hz - with Display Menu I can change to 60Hz - so Hardware and Software do support it - just not Apple Native Software - such crap! https://apps.apple.com/de/app/display-menu/id549083868?mt=12

I have found a temporary solution.

I had the same problems as everyone else with my Benq SW271 external display: incorrect resolution, refresh rate limited to 30 Hz instead of 60 Hz, poor image quality. My screen was plugged in with a usb-c cable. Today I used a Belkin usb-c to hdmi adapter and it works fine (4k and 60Hz). 

I know this is just a workaround and the real solution has to come from Apple. So we still have to continue to put pressure on Apple by calling customer service and reporting the problem here: https://www.apple.com/feedback/macos.html

[Edited by Moderator]

I had the same problems as everyone else with my Lg 32 4K Ud99 external display: incorrect resolution, refresh rate limited to 30 Hz instead of 60 Hz, poor image quality. My screen was plugged in with a usb-c cable. 

The real solution has to come from Apple. 

So we still have to continue to put pressure on Apple by calling customer service and reporting the problem here: https://www.apple.com/feedback/macos.html

Agreed. As I pointed out in this post, no external hardware or software solution can or will fix this problem. No "trick" will work. macOS fails at detecting the correct displays and display modes. No external solution can possibly fix that. People need to stop plugging those silly solutions. They are taking people for a ride, wasting their time and money. Only Apple can fix this issue. Apple should fix this issue quickly.

I've updated this morning from 11.2.1 to 11.2.2, closed all windows, programs, etc and rebooted (with monitor connected via USB-C cable - this is a DELL 27''), but still I have the message that 'no USB-C signal is detected by the monitor'. This is when I use my newer MacBook Pro (13-inch, M1, 2020, 16 GB memory, OS: Big Sur 11.2.2). If I try with my older MacBook 11-inch laptop (running Catalina - I've decided not to update it for now) I have no problem whatsoever to connect the same monitor with the same USB-C cable. I filed a bug report using https://www.apple.com/feedback/macos.html

Apple doesn't read this thread. If you want this problem fixed, you have to put pressure on Apple. So call customer service and report the problem here: https://www.apple.com/feedback/macos.html Do both: call and write.

As you can see from this tread, there must be a huge nr of people suffering from some variation of this issue since 'upgrading' from Catalina to Big Sur. As someone else suggested, and I have now done, post your issue of the apple feedback form here

https://www.apple.com/feedback/macos.html God knows if it will do any good, but seems any fix is in the hands of Apple. Might be time to take to Twitter to raise the profile.... @tim_cook & @apple ?

For me my problem is that my MB PRO 2017 will still work with a Cinema screen & a Viewsonic, but if I try running Zoom meeting, it starts to slow to a crawl and activity monitor shows the CPU taking a hammering from Kernel_task, Windowserver and Google chrome helper....

To use Zoom now I have to unplug the 2 external monitors...which makes showing multiple tabs in chrome/safai during a meeting/webinar is now a real pain....

When not using Zoom the screens do work for day to day stuff, I have main screen with Chrome multiple tabs, another screen using Safari for social media/news/youtube & the laptop with a few odds & sods other email a/c's and now ACTIVITY MONITOR...!

Sometimes through the day (no zoom running) it all struggles for a few mins here and there, especially if watching something on YouTube......so my manifestation of whatever is happening is not as extreme as others posting here, but still a real pain, considering it has all been very good for years....!

This fixed my "No Signal/No external display detected" issue.

It's a setting of your monitor. For my Dell 4K, it requires press and hold on one of the physical buttons on the monitor. You can check with your monitor user's manual. 

Here is a link to my earlier post.

https://discussions.apple.com/thread/252174979?answerId=254843026022#254843026022

Hi everybody,

I updated my MacBook Pro yesterday and I woke up today with the same problem as you, after trying many things, this worked:

https://support.apple.com/en-us/HT210742

I basically changed the Resolution of my external monitor, choosing an option from the SCALED menu.

Hope this works!