External Display USB-c Monitor issue

Hi Alan, thanks for providing that. I did eventually finally find the following for folks using the M1 Mini to connect to the LG Ultrafine 4K or 5K with Thunderbolt. I will test these as soon as they arrive later today and provide feedback. These are as of yet untested.

HDMI to USB-C dongle:

https://www.amazon.com/gp/product/B083YYFLLB/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&psc=1

HDMI 2.0 cable:

https://www.amazon.com/gp/product/B07X4W3VF5/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&psc=1

I just ordered this and hoping for an improvement:

Cable Matters USB C to DisplayPort Cable (USB-C to DisplayPort Cable, USB C to DP Cable) Supporting 8K 60Hz in Black 6 ft - Thunderbolt 3 Port Compatible with MacBook Pro, Dell XPS 13 and More https://smile.amazon.com/dp/B01J6DT070/ref=cm_sw_r_cp_api_glt_fabc_W0HFHC5DT2WDX2PY0A2S

Have you called Apple Support? And did you try to change some settings on the external display like Display Port version (mine is 1.4)?

FYI, my MBA M1 with 11.2.1 and LG650UL connected via DisplayPort (version 1.4) to Type-C cable still works fine over a week now. By fine I mean 4K@60hz.

TO EVERYONE — IF YOU STILL HAVE THIS ISSUE, CALL APPLE SUPPORT AS:

1) THEY MAY HELP YOU;

2) IF THE DON'T, THEY WILL KNOW ABOUT THIS ISSUE AND RAISE IT UP TO THE ENGINEERS.

AFTER THIS, POST THE ISSUE ID TO GATHER ALL REGISTERED ISSUES IN APPLE SUPPORT.

FYI a flagship MacBook Pro 16", their yet best professional series laptop with a dedicated GPU connected to a $1.3k professional series display behaves as a midrange laptop with a $150 external display. It doesn't recognise the BenQ display no matter what cable configuration is used. I have already been in touch with BenQ support and they have confirmed this is an Apple issue. I have also spoken to Mac support on 27th of Dec. They SHOULD be aware of the issue, as I have never seen more elaborative forum posts on any other issue for any other OS and I have been in the industry for 25 years. I feel that their engineering and software teams' competence leaves a lot to be desired from.

I am dumbfounded how this is not fixed for so long. It seems that the root cause may be too deep in the Big Sur's core code.. maybe it is there on purpose to protect their M1 from driving few UHD screens.. Although seemingly a productive chip by Apple's own tests and measurements, it may be a lacking chip to drive multiple displays and Big Sur is consciously limiting the external screen capabilities as it is already driving the 3072x1920 builtin display in my case. This could be farfetched but unfortunately I cannot find any logical explanation for Apple's lack of reply other than the above or the complete inadequacy of their engineering.

This is a direct quote from BenQ's support again for visibility:

Hello,

Thanks for contacting BenQ Support. We have determined the issue is definitely with the operating system. BenQ has been working on investigating this issue, and we will keep our customers informed once the root cause is being identified. At the meantime, we also suggest you reach out to Apple support team for further assistance. Thank you for your patience with us! The SW271 will work at 1080p or 4K@30hz via usb-c.

Warm Regards,

BenQ Support

TO EVERYONE — IF YOU STILL HAVE THIS ISSUE, CALL APPLE SUPPORT AS:

1) THEY MAY HELP YOU;

2) IF THE DON'T, THEY WILL KNOW ABOUT THIS ISSUE AND RAISE IT UP TO THE ENGINEERS. AFTER THIS, POST THE ISSUE ID HERE.

Please stop just saying "it still doesn't work". The best thing you can do right now is to inform Apple and/or your display manufacturer about this issue by contacting their support.

Did you already call to Apple Support about this? To let them try to help and to raise awareness of this issue.

I tried to reset NVRAM (Restart your computer, press and hold CMD+OPTION+R+P until it restarts for the second time). It kind of helped — when my external display was working along with open MacBook's display I saw the good old 4K@60 but when I closed the lid, it became 30 again. Since then this trick doesn't help. But you can try. But it's definitely the OS problem. A HUGE PROBLEM FOR THOSE WHO BUY $2000 LAPTOP TO WORK WITH AN EXTERNAL DISPLAY.

If one need a workaround one can try to connect the display via HDMI, it should work.

I am having a problem with my M1 MBA recognizing the external monitor connected to the second USB-C port on the laptop. One strange fix is this: I have an Anker dongle connected to the power USB-C port. If I disconnect that dongle, the Mac is much more likely to recognize the display. Then I can reconnect the dongle and it continues to work. Weird and annoying. One theory is that the mere presence of the unused HDMI port on the dongle is confusing the Mac about where to look for a display. Yes, I am aware the M1 MBA supports only one eternal display. I am not trying to use 2. I am referring to an unused HDMI port.

I have just bought a new MBA M1 and now it's working fine with my external monitor LG27UL550 in 4K@60 mode via USB-C-to-DisplayPort. Big Sur is 11.0. I won't upgrade it anytime soon as I think this problem about versions above 11.0. If you have Big Sur 11.0+ try to downgrade to 11.0.

I have a similar issue mba m1 using usb c to a dell curved. once it sleeps the bt kb will wake the laptop but not the external monitor. I have given up calling apple support they totally ignore the issue. I open the m1 lid, wait 5 seconds for the monitor to come on, close the lid and continue working. on the plus side homebrew, printer drivers, scanner drivers etc are working on m1. transmit is arm native, etc. so taking a dive into arm knowing it wasn't going to be perfect isn't as bad as it could be.

my LG screen connected via usb-c now wakes up after touching keyboard or mouse since 11.1

half of the problem solved for me...

other part unsolved is sometimes it wakes up in the wrong resolution, have to fix it manually through settings

I just received and tested out an HDMI to USB-C cable. The only thing it improved was waking of my external monitor. With DisplayPort it usually won't wake on its own when I wake the MacBook. With the new HDMI to USB-C cable it consistently wakes every time. What still isn't consistent is remembering the display scaling settings. To make matters worse the image is a little washed out regardless of settings (including using the correct color profile). On top of that the screen brightness setting on my MacBook acts very strange when using the monitor and this cable. It's not remembering my preferred brightness level, and wakes either at full brightness, or way below half.

What a mess.

K so the problem seems to mostly be with MacBooks with intel processors (not the Apple M1 chip) who have updated to Big Sur or done any of the Big Sur updates.

Here are the cable configurations that worked/didn’t work for me from my Mac to my monitor :

❌usb-c to usb-c

❌usb-c to usb-a female with usb-a male to microusb

❌(off-brand) usb-c port to hdmi/hdmi

✅usb-c to hdmi cable

✅Apple usb-c port to hdmi/hdmi

I have a 2020 MacBook Pro and I use a NewSoul portable monitor that worked perfectly fine with a usb-c to usb-c connection up until the Big Sur 11.2.1 update where it stopped displaying anything at all. My Mac only recognized it as a power source, not a display. (I tried a PRAM reset, SMC reset, safe mode, etc...)

I tried an off-brand usb-c port that doesn’t usually need any drivers EXCEPT FOR BIG SUR (according to their chat support). And the Big Sur drivers don’t exist yet for the ports I needed 🤦🏻‍♀️ so I got an open box Apple usb-c to Digital AV port for $15 off at Best Buy which works perfectly! 🙌

Basically the Big Sur update messed everything up and it seems their fixes keep messing different things up. So either back everything up and revert to Catalina or get some new cables/ports. Hope this helps someone!

11.2 beta is out — the ones who already experience this issue should try it I guess.

There is a macOS Big Sur 11.2 update that came out on Monday, February 1, 2021 though.