Big Sur 11.1 External Display Issues!

The same issue with my MBP 16" connected to a 32in LG 4K-UHD (LG 32UD99-W).

While burning the firmware with newly "Bug Sur" 11.1 I even got a message from my LG stating that the resolution's changing to - hold an believe - "1920x1080" and I should change the resolution to "3840x2160" for a more comfort ...

In this discussion https://discussions.apple.com/thread/250715148 I found a reference to "DisableMonitor 1.92".

I tried this workaround and it worked for me ...

Please can someone check whether or not the workaround with "DisableMonitor 1.92" - https://github.com/eun/disablemonitor - works til Apple improves "Bug Sur" 11.1 ...

Same here:

Before 11.1 - no issues. display correctly identified and able to display native resolution with HDR enabled

After 11.1 - display not recognized correctly after. Native resolutions incorrect. Max resolution 1080p with 30Hz refresh rate.

My temporary workaround incl. HDR enabled:

in System Preferences

-> Display Settings

-> Option-Click on Scaled.

-> Click checkbox "Show low-res modes".

-> Choose your native display resolution.

-> Refresh rate dropdown still greyed out and shows 30Hz.

-> Display should run on native res @30Hz now. Unplug you USB-C cable from computer and put it back it.

-> Correct native resolution is still active and refresh rate dropdown is not greyed out anymore. change it to your native setting like 60Hz. DONE.

I have to do this every time my Macbook Pro 16" falls into sleep. I extended the screensaver time so it works for me for an entire workday. I have to do this workaround only once in the morning which is not ideal but fine for some time now.

Hello,

I may have a solution to your problem. There are brands of adapters that are plug and play with no drivers. Although there are some that need a driver to run the adapter. Now, I have a MacBook Air from late 2017 that I upgraded to Big Sur and the adapter no longer worked (I have a adapter that needs a driver). I contacted the company and they said they needed to make a new driver because of problems with the new OS and their current driver. It seems to me that MacOS Big Sur might have had some compatibility issues. If I may ask, do you know what brand your adapter is? Do you know if it needs a driver? Reply with the model number and brand if you want and I can probably help you more.

NG_5

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

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!

If you read through the discussion, there’s no solution as it is a bug in big sur 11.1 which can’t be worked around.

I think there are only three things to do

1- leave a feedback on the apple area: https://www.apple.com/feedback/

2- call the technical support so they know how many people are having the issue

3- pray issue will be solved soon

The same issues started after installing Big Sur 11.1 on a MacBook Pro (15-inch, 2017) with LG 34UM95-P monitor. After trying many suggestions, the final solution was to go into LG monitor settings and enable DisplayPort 1.2.

Note that I also use Boot Camp and Windows had no problems detecting the external display. So, it doesn't seem to be computer hardware, monitor, or cabling issue.

I'm confirming, again, that restarting my computer by only holding down the physical power button on the keyboard is working for me to fix this problem, daily. I'm not holding down any other key on the keyboard, just the power button to shut off and again to turn on. Seems like a desperate move, but it is working for me.

MacBook Pro (16-inch, 2019)

It's not without momentary display glitches once in a while, like pixelated, fragmented, or strange bright green colors on some images when dragging them from built in display to the external. For the most part it's for a split second. And rarely, the glitches remain with viewing files in Photoshop like gray blank spots, then when I drag to the built in display, the file is ok.

To add my pennies to this thread.

I'm using a BenQ SW271 on a 2020 5k iMac using Big Sur 11.1

I have most the problems described in this thread. Initially with the USB C to USB C cable supplied with the BenQ, then with a Benfei Thunderbolt 3 to Display port cable and finally a Moshi USB C to Display Port cable as recommended by Apple support.

What I have come to realise is that the problem is with the USB/Thunderbolt interface on the iMac. When the problem occurs - whenever first booted or when power save mode turns off the displays - I have only to removed the USB C / Thunderbolt connector from the iMac, wait 3 - 4 seconds and then reconnect. No other actions necessary on the BenQ or with the Display Port connector. On reconnecting the iMac recognises the BenQ and restores the display at native resolution (3840 x 2160) using 60Hz refresh. All is then well until the next time I reboot or power-save mode starts.

Andy

Try this guys, it works every time for me !

Macbook pro 16"

LG hdr 27"

BenQ EW327OU 32"

Step 1:

System Preferences -> Display

> HDMI Monitor -> Color ->

Calibrate... -> Click through all

the dialogs, Done!

Step 2:

Modify resolution on any different resolution in order to make the screen of the faulty monitor respond:

System preference/Displays.

If you don't see the resolution window of the faulty monitor then click to "Gather windows" and it will show up.

Step 3:

If the problem remain just unplug/plug in the monitor who have issues.

Let me know if it has work for you too, i hope this help.

I applied the macOS 11.2 update as well. I powered everything down after the update (turned off all power strips), reset my monitor settings to factory (I use a 34" LG 5K2K display), reset the SMC and switched back to the Owens Corning optical Thunderbolt 3 cable. I'm back to full 5120 x 2160 resolution at 60Hz.

I have to test my other OS partition running 10.15.7 and will update this thread if I see problems there. This bug has been a HUGE pain, but 11.2 is promising so far.

If you read through the thread you will find there are workarounds.

For me - Using 2020 MBP16 and TB3 to HDMI 4k 60hz (!) adapter from Satechi solved it. Lost HDR but dont care. its functioning reliably. Also pointing out it has to be the 60hz one, as the cheaper ones are 30hz only.

Installed 11.2 today on my iMac 2020 that has a BenQ SW271 connected via a USB C to USB C cable that came with the BenQ.

I've now power cycled the iMac and BenQ three times and each time on restarting it has successfully detected the BenQ and configured the interface for 3840 x 2160 @ 60Hz. I've got the BenQ now configured for Display Port 1.4 support too.

The issues with 'No signal detected' / 60Hz not available / HDR mode being enabled, fingers-crossed, seem to have gone with the update to 11.2.

I hope this continues as this problem has been really, really frustrating.

Andy

For me, the problem was not fixed after upgrading from macOS Big Sur 11.1 to macOS Big Sur 11.2.

macOS Big Sur 11.2 on MacBook Pro (16-inch, 2019) does not detect the correct display modes for the Philips 346P1CRH/00 display, allowing only non-native display modes. This problem does not exist on earlier macOS versions or on other operating systems.

I contacted Apple support multiple times about this, since the introduction of this problem with the release macOS Big Sur 11.1. Still no fix. No communication from Apple about this issue either, even though it affects many customers. I will have to downgrade to macOS Catalina 10.15. This is very disappointing.

Today I installed macOS 11.2 on a MBP 16“ with an external monitor USB-C LG 32UD99-W.

The ‚highest‘ resolution in the external monitor is now „1080p“ (1920 x 1080, 60 Hz) whereas before I used to use a resolution of 2880 x 1620, 60 Hz, or higher. The same problem plagued me already with 11.1 (and the last version that worked was 11.0.1).

From Apples support on Twitter I got the following tips for a "temporary" workaround:

a.) Reset the windowsever by removing a couple files. Please open Finder and from the menu bar select Go > Go To Folder to locate the following:

/Library/Preferences/com.apple.windowserver.plist

~/Library/Preferences/ByHost/com.apple.windowserver.XXXXX.plist (not always there)

Note: "XXXXXX" in the example above represents a variable string of letters and numbers.

b.) Please move those files to the trash. Then restart and reset the NVRAM using the steps found here: https://s.apple.com/dE4l1d7i4H

After performing the two steps as advised System Preferences > Display shows me more/all missing resolutions.

But the clocking (Hz) isn't correct (still to low) and after a reboot I have to perform the mentioned to steps again ...