M1 Mac Mini, Displays wont turn on after wake from sleep

Disabling sleep does not work. I have seen this posted multiple times. I have disabled sleep in an effort to get my LG Widescreen monitor to be awakened by my M1 Mac Mini as well as tried every other way to get this to work and it just flat out doesn't work. Apple has a bug on their hands with this. I would advise against ANYONE buying the new M1 Mac Mini until Apple can address this issue. Any "time saved" by the processing boost of the M1 chip is more than offset by the constant rebooting and plugging-unplugging monitor cables all day just to get your desktop back when you step away for longer than 15 minutes.

You are not alone. There are several people having big issues with the Mac mini M1 connected to multiple monitors, and so far no solution. There is no response from Apple and nobody could find a configuration that works. Check this post.

https://discussions.apple.com/thread/252072263

Here is a video of what my Mac mini M1 does when I turn it off and on again

https://youtu.be/v1gpgcLzOCY

Glad to hear they got back to you.

My problem's different though. I was getting a "sleepy" monitor occasionally - same as OP (so far it's been waking 100% since ticked then unticked Mirror Displays checkbox in displays setting). It's a non-DisplayLink Dell 2515H monitor connected via USB-C's 9in1 UGREEN HUB that has one HDMI port. Thus this monitor is deemed as a native external and the only allowed on M1 machines up to 6K. When it didn't wake up from sleep the monitor disappeared from my Displays completely and only two actions would bring it back:

1. Unplugging and replugging all USB-C hubs including one with other DisplayLink monitors (unplugging HDMI from the hub didn't help)
2. OS X reboot also solves the problem

The problem was also occurring on a fresh install of OS X Big Sur 11.1 with SSD reformat with no DisplayLink driver/other monitors connected. I tested with one Dell 2515H monitor connected via three adapters - Satechi Dual HDMI at 60Hz, UGREEN 9in1 and simple UGREEN USB-C to HDMI only adapter. I'm using quality Neet 2.0b HDMI cables and have swapped them to rule out bad cables.

Well, my problem seems to have disappeared. I've tried a few different things since I last posted, and can't really tell you which of these things, if any of them, fixed the problem... but the problem seems to be fixed for now. Heres is what I have tried:

1. I still have that XPUS adapter plugged in that was referenced above. It has a lot of ports, so I just kept it plugged in even though it didn't solve the problem initially.
2. I had to click "mirror screens" to do some work-related tasks, then unchecked it when I was done. I note this because others have mentioned clicking then unchecking this box has helped them.
3. I have turned off wifi. I read in another thread that the wifi radio may be causing interference with Bluetooth, so I turned off wifi because my bluetooth keyboard kept having difficulty staying connected. Since then, the keyboard stays connected with zero problems. It was also eating through batteries with the M1, so this may hopefully solve that problem too. I know this isn't an option for everyone, and that it also prevents me from logging in with my watch, but it's a feature that I just started using, so I won't miss it much.

Again, I don't know which of these things fixed my wake-from-sleep problem, or if any of them actually had anything to do with it, but everything seems to be working fine, so I'm not changing anything out until the next update.

Hope this helps.

Just wanted to add to the record:

• M1 mini 16 GB
• new LG 27UN850-W monitor, connected via USB-C to USB-C
• Bluetooth keyboard and mouse, no apparent issues with those so far
• ethernet only (wifi off)

I've only had the mini for a few days, so I haven't done much testing of different settings or cables (and am loathe to switch to HDMI and lose HDR capability). When the mini sleeps normally during the day, no issues with display waking from sleep. However, when left to sleep overnight, display doesn't wake up, I need to unplug and re-plug the cable. I haven't given it it much time to wake in the morning, so perhaps I need to be more patient? Also I need to see if changing DisplayPort version from 1.4 down to 1.2 will make any difference (again, wouldn't be a huge fan of this solution b/c I'd lose HDR), or if turning monitor off at night matters.

I'm new to Macs, but should there be any difference between sleeping for an hour or two, and overnight sleep? It just seems odd that I'm getting a different result from the longer sleep. Am I trying to wake the mini from REM or something? Do I need to throw off its covers, open its curtains, then wait to see what happens? So far, the mini seems to be fantastic otherwise, if I can't figure this out, I'm debating whether to return (I have until 2 Feb to decide) or keep it and deal with it until a - OS? firmware? - solution is implemented, maybe just shut down at night as a compromise? I really don't want to go back to MS/Windows!

I'm rather pessimistic and doubt they'll solve the actual problem for those of us not using DVI converter as they're very specific who should benefit from the update but we'll see anyway - thanks for posting this useful info and fingers crossed!

Just a quick update after a couple of weeks update and reading this forum's messages with other solutions:

• ticking and unticking Mirror Displays in Displays in System Preferences doesn't solve the problem and the sleepy monitor reoccured for me. I try not to touch anything (mouse/keyboard) and only use power/touch ID button to wake my MBA 13 M1 2020 - 80-90% of time it's waking my HDMI native monitor fine but it's still not 100% as my other 4 DisplayLink monitors that are alway waking up properly.
• moving very rapidly mouse so the cursor "inflates" solution posted by someone here has never worked for me

> My understanding was that 11.2 was supposed to address the sleep issue but it didn't work in my case.

The "fix" was limited to:

• External displays may show a black screen when connected to a Mac mini (M1, 2020) using an HDMI to DVI converter

"Anyone else with no-wake issues on an M1 Mac mini" - Thread full of people reporting issues, so that would be a yes! 😊

What you didn't mention, in your post, is the connection type you are using. In general, you will find that people using HDMI to HDMI cables, Mac to monitor, are having the least issues. Those using USB-C to DisplayPort seem to have a lot of issues. Any type of conversion cable, or adapter, seems to add to the issues.

In my case, using HDMI to HDMI with a Alienware monitor resulted in the waking problem. This was my initial setup, back in December. I very soon upgraded to an LG 4k monitor, still using HDMI to HDMI, and never had the wake issue again.

With that said, at times, my LG monitor would be slow to wake up. Nothing more than a few seconds, but long enough to make me wonder. On the plus side, this latest Big Sur update cured that problem. Now, if I move the mouse, or tough the keyboard, the monitor is quick to come to life.

If you digest the various posts here, and on Reddit, regarding the monitor wake problem, there are a few steps to try.

• Use an HDMI to HDMI cable
• Unplug any USB-A and USB-C devices that you can do without for testing
• If you have a USB-A or USB-C you can't unplug, use the port furthest away from your HDMI port

Try those and see if you have any success. Best of luck with it.

For me, as I know the device is very low power already, I have 'solved' the issue with the following settings.

1. In Energy Control panel, enable all options (prevent,hard disks,wake,start up).
2. Set turn display off after 15 mins.
3. Enable a hot corner to turn the displays off whenever I want.

So basically, the machine is on all the time. I have not measured the TDP of idle, but I expect it is sipping anyway. Having the monitors off whenever I'm not using it is more of a concern, and this works well. I have never had the issue with these settings. I will play with it again maybe on the next release!

I have a similar problem but a slightly more complicated setup. I have a brand new M1 Mac Mini running OS X 12.0.1 and an older late 2014 Mac Mini running OS X 11.6. These are both connected to a StarTech SV4312DUA KVM switch (along with a ThinkPad Ultra dock and a Linux tower PC). The Mac's both have problems when switching the KVM to them and waking the displays. The New M1 is worst. Windows and Linux work perfectly.

The StarTech has DVI -> HDMI for both screens which are identical.

Old Mac Mini:

• Mini-display port -> DVI on StarTech KVM
• HDMI -> DVI on StarTech KVM
• The behaviour is that the screens either come on correctly and work fine, or the system cycles through a range of possible screen configurations with screens coming on and off and the signal from the Mac coming and going (making the screen report no input) and finally settles into a single config, usually with the correct setup. Sometimes it gets it wrong and gives me just one screen and then relocates all my open windows to that screen (usually a lot of windows across multiple spaces!). This is a huge productivity killer!

New M1 Mac Mini:

• HDMI -> DVI on StarTech KVM
• USB C -> DVI on StarTech KVM
• The behaviour here is more straightforward - it simply doesn't bring up the USB C screen on almost all occasions and relocates all my open windows. Very occasionally it works and brings up both displays where I left off but this is only (and only sometimes) when I have switched the KVM to another machine and switched back before enough time has elapsed for screen-savers or display sleep to activate (though maybe display ports sleep when the screens are switched away).

As I noted above, Windows on the ThinkPad and Linux on a custom-built tower PC both work perfectly (ThinkPad has USB C to the Ultra dock and then Display Port and HDMI to the StarTech KVM; Linux PC has two DVI interfaces direct to the StarTech KVM).

Apple have had a long-standing problem with displays and it looks to me they need to rewrite the display drivers entirely - it's just one bug layered on another as they try to fix this.

As said before not a single time since yesterday have had this problem after ticking then unticking "Mirror Displays" checkbox in Preferences > Displays > Arrangement tab - maybe this is a workaround for some and this forum has solved my problem after all - time will tell and will report back in a couple of weeks time.

A quality HDMI 4k-8k cable from Belkin HDMI 2.1 solved all my problems. Cheap cables seemed to work but created a lot of problems and interference.you need a cable that supports HDR

I have a similar issue. Only one display connected - Apple Pro XDR. Sometimes, even if the screen wakes up, I'm unable to sign back in as the mouse and keyboard are not recognised. Briefly pressing the power button seems to resolve the issue. Also unable to have my Apple Watch unlock the Mac even though security settings say it's enabled.

For the time being, until my LG 32 inch Ergo arrives, I have an Acer K227HUL display connected to the M1 mini via HDMI. If the screen saver is present, either magic keyboard, or magic mouse 2 will wake it. If black screen after screen saver has ended, then only a single click from the magic mouse 2 will wake it after several seconds of delay.

These may be issues resolved in the next Big Sur update.