HDMI Port No Longer Working After Update to macOS 11 Big Sur

[triangletechie]

I just got the Mac mini and have a monitor hooked up via HDMI. Worked fine for a couple days and then I got a no HDMI signal display. Had to reconnect the HDMI cable and it came back on. So frustrating when the simplest things still don't work consistently.

 

[Kidas]

Hi I had the same issue. (Mac Mini 2018 + 4k over USB-C + 4k over HDMI).

Initially on upgrade to Big Sur, the HDMI port did not work. Tried multiple cables and switched between monitors. NO joy. Just black screens and (apparently) no output signal from HDMI.

I re-started a couple of times.Searched the web; got frustrated.

Then tried switching off; disconnected all monitors; connected just one using the HDMI-HDMI cable.
It took longer to crank up than normal, and there was no Apple logo and progress bar, but after a couple of minutes, the screen lit up.
I was the default resolution and background, but I fixed those.
Then added the second monitor over USB-C.
Reset the resolutions and monitor arrangement.
All good.

Then re-started, and (surprisingly) it all worked.
The Apple and progress bar started out on the USB screen, but switched half-way through to the HDMI screen. and since then, it seems OK.

Have re-started a couple of times since and it's all good -- the only strange thing is that during start-up the Apple logo and progress bar do odd things in terms of size and screen location -- presumably as different drivers are loaded during start-up

Hope it helps

D

 

[chicojobs]

Guys, same thing here: Mac Mini 2018, “old” non Retina LG monitor (2010-ish), everything worked fine up until last Sunday.

I don’t remember if I had automatic updates on but after 11.0.1 it all stop working.

The screen is on and functioning just before the login screen: it then “flashes” and it goes into HDMI Power Saving Mode (which I interpret as no signal)

When hooked up to a Sony 4K TV, both Mac Mini and the same HDMI cable work ok.

Unfortunately no luck with the USB-C>HDMI adaptor and no luck with big Sur 11.1 beta either.

I’m quite desperate honestly and I’d really avoid buying a new monitor...

 

[triangletechie]

I just got a new Dell QHD monitor to try out with the M1 mini. Same issue. Once the display goes blank, I consistently get the no HDMI signal message. Why, in late 2020, are we still having HDMI issues with Macs? I've only ever gotten this issue with Macs but not once on a Windows machine.

 

[Gabriel14]

OK, I've tried every cable connection in the thread including Daisy Chain.
Applecare can't fix it, monitor manufactures suggestions don't work. Drawer full of Amazon cables. Returned Mac suggested LG 5K for two BenQ2700U. Instead of dimming at night to lowest setting and hoping they don't burn out in 8 months.
All week everything works fine IF, I turn off display at night and come back to work and turn both displays on at the same time via power button. Still do arrangement through system preferences but how happy to find it working.

 

[Gst95]

I'm also having the same issue after updating to Big Sur, on my Macbook Pro Retina '15 (2013 model). Neither the HDMI or the USB slots seem to be working whatsoever, no detection of any second display, absolutely nothing.

A fix for this would really be convenient ASAP.

 

[amondror]

I just updated my Mac mini 2018 to Big Sur, and the HDMI port no longer works.



I have a dual 4K monitor setup which has worked fine since I bought the computer.

Monitor 1: HDMI to HDMI

Monitor 2: USB-C/Thunderbolt to DisplayPort

Both monitors are the same brand/model.



Upon first boot into Big Sur after the update, one monitor wasn't working (the one with HDMI).



Troubleshooting I have done:

• Confirmed the HDMI cable is fine (it works with another computer and the other monitor)
• Unplugged all peripherals except for the HDMI monitor (result: no output)
• HDMI monitor not showing up in Display settings

Troubleshooting done with Apple Support:

• Reset NVRAM & PRAM
• Reset SMC
• Diagnostics Test (result: no issues found)

I will be doing a downgrade and Time Machine restore to Catalina in the next couple days to see if the Big Sur update broke the HDMI port, or if it’s a hardware issue.



>> Has anyone had a similar issue? Is there anything else I could try to get the HDMI port working before restoring?

I found this https://www.resourcesforlife.com/docs/item31391 didn’t fix the problem

 

[amondror]

I just updated my Mac mini 2018 to Big Sur, and the HDMI port no longer works.



I have a dual 4K monitor setup which has worked fine since I bought the computer.

Monitor 1: HDMI to HDMI

Monitor 2: USB-C/Thunderbolt to DisplayPort

Both monitors are the same brand/model.



Upon first boot into Big Sur after the update, one monitor wasn't working (the one with HDMI).



Troubleshooting I have done:

• Confirmed the HDMI cable is fine (it works with another computer and the other monitor)
• Unplugged all peripherals except for the HDMI monitor (result: no output)
• HDMI monitor not showing up in Display settings

Troubleshooting done with Apple Support:

• Reset NVRAM & PRAM
• Reset SMC
• Diagnostics Test (result: no issues found)

I will be doing a downgrade and Time Machine restore to Catalina in the next couple days to see if the Big Sur update broke the HDMI port, or if it’s a hardware issue.



>> Has anyone had a similar issue? Is there anything else I could try to get the HDMI port working before restoring?

Fixed by unplug all the monitors including egpu rx580 in akitio, plug only one monitor to the egpu, start working,

 

[ilpap]

11.2 Beta (20D5029f) and still the HDMI does not function.

edit #1: However, connecting both monitors via USB-C seems to work now. This didn't work well in the past as I am using a 5K and a 4K monitor at the same time.
It works today though. Let's see tomorrow.

edit #2: Its amazing how crappy the software is here. After playing around randomly with the cables indeed both monitors were on, and the Sys Preferences showed that they run on default resolution. BUT, the LG 5K was definitely a bit blurry on the text, not crisp as usual.
I removed the LG4K, and the 5K was back to normal, crisp at a retina level of quality.

I plugged in the LG4K, and of course, it doesn't turn on again.

 

[djc6]

Odd, the problems described in this thread are my experience under Catalina - since upgrading to Big Sur my 2x LG 4K monitors finally work properly: https://forums.macrumors.com/threads/big-sur-11-1-fixed-my-monitor-issues.2275729/

I feel like half? 2/3rds? of threads in this forum are monitor issues!

 

[amondror]

Mac mini 2018 with three monitors, two from eGPU one directly. After the update only the directly monitor worked, I unplug all the monitors and plug one by one back. I found the eGPU working only with one monitor. I plug the second monitor to usb c. Back to normal.

 

[glowfish]

I've got the same issues with the Satechi iMac Desktop Aluminum USB-C Monitor Stand. Everything worked fine under Catalina, but it no longer works under Big Sur - device no longer provides power to the front ports. It's about as useful as a $100 phone book now.

 

[jazz1]

I've got the same issues with the Satechi iMac Desktop Aluminum USB-C Monitor Stand. Everything worked fine under Catalina, but it no longer works under Big Sur - device no longer provides power to the front ports. It's about as useful as a $100 phone book now.

Darn, that looks like a nice set-up. I'd add one to my iMac once it gets sorted out. Please let us know if the issue gets resolved.

 

[amondror]

I using egpu radon rx850 with Mac mini 2018 after I update from 11.01 to 11.1 the egpu was registered by the Mac but no display. I reinstall back (time machine) 10.15.7 and the rx850 back to live. I install back 11.1 directly in this time the rx850 continue working ok.

 

[Geogol]

I just updated my Mac mini 2018 to Big Sur, and the HDMI port no longer works.



I have a dual 4K monitor setup which has worked fine since I bought the computer.

Monitor 1: HDMI to HDMI

Monitor 2: USB-C/Thunderbolt to DisplayPort

Both monitors are the same brand/model.



Upon first boot into Big Sur after the update, one monitor wasn't working (the one with HDMI).



Troubleshooting I have done:

• Confirmed the HDMI cable is fine (it works with another computer and the other monitor)
• Unplugged all peripherals except for the HDMI monitor (result: no output)
• HDMI monitor not showing up in Display settings

Troubleshooting done with Apple Support:

• Reset NVRAM & PRAM
• Reset SMC
• Diagnostics Test (result: no issues found)

I will be doing a downgrade and Time Machine restore to Catalina in the next couple days to see if the Big Sur update broke the HDMI port, or if it’s a hardware issue.



>> Has anyone had a similar issue? Is there anything else I could try to get the HDMI port working before restoring?

This what worked for me: 1) Turn off your mac mini. 2) Unplug your monitor with USB-C and leave only HDMI Monitor 3) Turn your mac mini and it will have to recognize your HDMI monitor 4) Plug in back your USC-C second monitor and all must work. Enjoy!

 

[amondror]

This what worked for me: 1) Turn off your mac mini. 2) Unplug your monitor with USB-C and leave only HDMI Monitor 3) Turn your mac mini and it will have to recognize your HDMI monitor 4) Plug in back your USC-C second monitor and all must work. Enjoy!

Reinstall 10.15 and install back 11.1 fixed the problem.

 

[Sundzvald]

This driver worked for me.. https://www.displaylink.com/downloads/file?id=1660

 

[michmcca]

Hello Sundzvald:

I tried installing DisplayLink Manager, but it doesn't improve my situation at all. I have a Visio 4K TV, hdmi interface only, connected to my Radeon RX 570. It makes a great monitor, and works fine on Catalina, but with Big Sur, it occasionally flickers on, and a second later off again. 99.9% of the time, it shows No Signal.

What is your configuration? Are you using a DisplayLink device?

Thank you very much.

 

[ashleykaryl]

I had this for the first time today with no obvious reason. After going out for a while I came back and found there was no signal via HDMI. Resetting the NVRAM seems to have fixed it for the moment.

Reset NVRAM on your Mac

If one or more settings stored in NVRAM aren't working as expected on an Intel-based Mac, resetting NVRAM may help.

support.apple.com

 

[bevberlin]

New Mac Mini M1. HDMI port fails when returning from monitor off and sleep. Screen filled with "snow" followed by solid magenta screen. Running Big Sur latest as of 12/26/20. My work-around solution - turn off sleep, monitor never turns off, screen saver always on after 10 minutes. As long as the hdmi port is producing output to the monitor, via screen saver and never turn off display, the display awakens normally every time i press a key. My opinion is there is a bug in the hdmi driver. I also noticed that turning the monitor off and on again restores normal function - before i configured as above. So either work-around works. Apple needs to fix this.

 

[petmrman]

Reinstall 10.15 and install back 11.1 fixed the problem.

Everything was all good on my Mac Mini (2018) until I decided to move 'up' to Big Sur. No Time Machine back-up before that (dumb, I know..) HDMI port not working after that install. I just followed @Geogol 's steps and this worked for me as well. So I guess I'll be unplugging USB-C monitor every time I power off the Mac Mini until Apple has a fix for this. @bevberlin indeed, I agree on your theory. @amondror : you advise to reinstall 10.15. Is this possible without Time Machine?

 

[bevberlin]

Also had a problem with an HDMI to DVI converter. I have two samsung monitors - one of them as a DVI port, and the other has HDMI. The one with the converter worked fine on my old Mac Mini 2012. When I switched to the M1 Mac Mini, there was absolutely no video at all. At first i thought the new Mini's HDMI port was defective, but i switched monitors, put the DVI version on my Ubuntu Linux computer, where it worked fine, and put the HDMI monitor on the M1 Mini, where it also worked fine. I don't know how the two port types differ in protocol and signal connections, So can't even form a hypothesis about why the converter doesn't work. But, it doesn't.

 

[dickovski]

Been using 3 dell monitors on 2018 Mac Mini with no problems even after upgrading to Big Sur. Then dropped a spirit level on one monitor (don't ask) and had to replace with a 4K Samsung yesterday. Connected it to HDMI port and it didn't work!

Messed around for ages swapping ports and cables and eventually got it to work but no idea how or why. Got in the office though this morning and it isn't recognised again. Worked through all the suggestions on here and what worked for me finally was

shutdown Mac
disconnect everything
startup with only the HDMI monitor connected
Once started up connect the 2 other monitors via USB C ports
A few secs of monitor flashing later and I have all 3 monitors working again at correct resolutions.

Will have to see in the morning if this sticks as I'm not shutting down my mac now - got work to do!!!

Hope this helps others and I'll report back in the morning

 

[OSXATL]

Had the same issue on my 2020 Intel i5 Mac mini, connected to 2 LG 27" 4K displays. The one connected via USB-C was working fine, but the one connected via HDMI wouldn't work at all.

Was able to solve it this way:

1) Shut down the computer.
2) Unplugged the USB-C connected display, leaving only the HDMI connected display.
3) Rebooted with Command - Option - P - R being held to reset the PRAM. Wait for 2nd restart chime, then stop holding keys.
4) On boot, the HDMI monitor is working again, and after logging in, connecting the USB-C connected display resulted in both displays working as they should.

 

[ilpap]

After installing the latest beta, both screens work on my Mac mini for the first time right away after the restart (no need to mess around with the cables).