Big Sur 11.1 External Display Issues!

I am now into my 3rd docking station which has given me some improvements.

Setup:

Dual 2k monitor setup, HP Z27n G2

Monitors connect to docking station, docking station to computer.

1 monitor connected with Displayport (protocol 1.2)

1 monitor connected with USB-C (Displayport alt mode)

(Only way for Mac to see both screens due to lack of Displayport MST)

Docking station: HP Thunderbolt 3 120W G2 dock.

This setup work with my MacBook Pro 13-inch 2019

This setup does NOT work with my MacBook Pro 15-inch 2018.

Based on all feedback on the thread I too believe it relates to firmware but likely also drivers.

One major difference between my to MacBooks is that my 15-inch has a Radeon 555X GPU, hence utilising GPU switching.

As soon as I plug the 15-inch to the dock the OS freezes. Shortly after a signal is established with one monitor (DP) and then disconnect again. Monitor connected with USB C never light up.

Have notified Apple of the same

It may be an EDID problem.

Is there anyone using the CalDigit dockingstrations as sold via the Apple website and having the same problems?

Is there anyone using a dock supporting DisplayLink having the same problems (note that the DisplayLink website has updated downloads available)

Did anyone try an EDID emulator?

Having the same issue too. Using the BENQ PD2720u. It's hit or miss. Sometimes it will recognize the native resolution but sometimes the highest it'll go is 1600 x 900. When it is acting up, I'll try fixing it with EasyRes or SwitchResX. With EasyRes, it will not display resolutions higher than 1600x900. With SwitchResX, I'll try forcing the monitor to switch to higher resolutions, like 2560x1440, but the graphics become very blurry and pixelated. Seems like this is an issue regardless of the monitor, but anyone specifically have this the BENQ PD2720U? If you do, any solutions?

I've also tried a new thunderbolt 3 cable and still the same issues. I've read that using the WARRKY Thunderbolt 3 to DisplayPort Cable fixes the issue, but I don't believe this method will charge you laptop if your monitor has charging capabilities.

Glad to know it seems to be a Big Sur issue (just really buggy OS overall). I was afraid that it's a monitor issue and would hate to go through the hassle of returning it.

I have found a temp solution for my BenQ EW3280U. I purchased a USBC to HDMI cable and directly connected to my laptop. After a PRAM reset, Both my LG 27 k5 and BenQ 32 are working. The BenQ lost the HDR capability on the Mac, but at least having it being usable again is huge. Here is a link to the cable: https://www.amazon.com/gp/product/B07C1MYDSD/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&psc=1

I couldn't agree more, plus the fact it is a complicated manoeuvre to restore the previous version of MacOS (I have terrabytes on my computer and restoring from time machine takes ages). They should not release such a change (whatever it was) without testing on different monitors!

Update: today I plugged a usb-c to DP cable. After a couple of connections I was able to set the display at 4K @60hz. I then disconnected the cable and used the thunderbolt3 cable an I’ve been able to do that again. Honestly don’t know why it worked. However, if I try to connect my XP PEN graphic display too, everything goes back to the original 30Hz condition.

So here's what happened to me. 3 days ago I connected a third monitor (2 monitors connected via usb c new one connected via HDMI) on Mac Mini i7. The next day I restarted and lost my HDMI monitor. Today Duke Energy showed up to upgrade my power meter they turned off the power to my house for 30 seconds turned it back on, all 3 monitors came back.

Maybe a reboot won't work but a full shut down, wait and then start up will help?

Hi,

FYI Today I went to a customer office and I've connected my MBP 16" to a Apple Pro Display XDR nanotexturized and worked like a **** full resolution, full speed ,full all . Hahahahaha Ok Apple I know now I need to waste 7,5K€ more , thanks!

MACBOOK PRO 16 2019 WORKAROUND / POSSIBLE SOLUTION

I also had the same issue when updating my MacBook Pro 16.

I am using a 32-inch curved Dell s3220 DGF with displayport version 1.4

I have tried restarting everything and reconnecting the cables which did not help. My MacBook wouldn't even recognize the monitor sometimes and when it did, would only allow me to select 800x600 resolution. The refresh rate is locked at 59.88 hertz as well. The few times I was able to open the drop down menu for the external display resolutions, once I would select 2k resolution, the screen would turn black to change resolutions (as normal) but would not come back on.

For some reason, when I go to the display preferences and select the "mirror displays" option, the external display gets recognized correctly. From there, I am able to select the correct resolution (2560x1440) and 165 hertz refresh rate with HDR, and then deselect the "mirror displays" option. This saved the correct display settings and worked for me. I wish I knew how this fixes the issue but no clue.

Hope this helps!

The nature of this bug is that sometimes external displays work but the majority of the time they don’t. I’ve seen many people post success and then come back and say it was a false alarm. I’ve gotten my hopes up a few times in my own experience.

I have exactly the same issues. I have an MB Air M1 and brand new MSI PS341WU. I have to connect directly from the Monitor's USB-C connection to the MB. Tried all the resets possible, no change. I also tried the Caldigit SOHO Dock via HDMI and DP - that made it worse as no connection was being picked up by the MB. Then I tried the Caldigit TS3 Dock and that was fine until the MB went to sleep and on awake the monitor is not recognised. This is just terrible Apple. We are down to one extra monitor for the new MBs (M1) and when the MB goes to sleep, the second monitor is not recognised on the awake. I seem to be going backwards with M1 and Apple.

Today I initialized my MBP16 HDD and made a clean Big Sur Installation.

After that, when I connected my BENQ PD2720u it was well recognized and worked fine. I rebooted and everything was still in place.

I connected then my XP-PEN Innovator 16 1080p. Everything continued to function.

I then tried to turn MBP off and on again...at first the BENQ was black. I switched it off and on an it was back but...guess what...at 30Hz!!! And the display arrangement was also cleared and I had to redo it again.

I'm having the same issue, but I couldn't work with 30Hz. I downloaded an app from the Mac App Store called display menu and I was able to set my first monitor to 4K scaled down to 1440p in 60Hz, and my second monitor to 2560x1440 in 59.9Hz. It's not the best solution because it looks a bit more pixelated, but I couldn't live with 30Hz.

Reinstalling Catalina did not work for me on a 2019 Mac Pro Rack. I tried two different Apple-branded graphics adapters (580MX and W5700X), one of which had never been installed in a Big Sur system, and still had the same problem with both.

I am having the same issue trying to connect MacBook to an old iMac using a Belkin DisplayPort cable. I managed to see the displays when I hooked it up to my Smart TV, but that was before I upgraded to BigSur 2 days ago. Big Sur is also causing issue with using my Snowball mic, which no longer works since upgrade. BigSur is a big disappointment so far. I don't get all the marketing hype. Belkin info says it's basically a breeze to set up. Try getting their Customer support on the weekend. God Luck. BTW, Apple Support says it's a Belkin issue, not theirs.