USB c display not waking from sleep on new Mac mini

Question

Level 1

5 points

USB c display not waking from sleep on new Mac mini

Hi,

I have recently moved from an ancient 2011 iMac to a new m1 Mini (16Gb, 1tB). I am having an issue with my usb c display not waking from sleep. If I unplug the usb c connection the monitor wakes, but the usb hub on the monitor does not (a pain as my keyboard/mouse are connected here). The monitor is also used with a Windows 10 laptop which has no issues, either over hdmi or usb c. The monitor is a Benq PD2704U 4k display, with a built-in KVM switch.

From what I have read this is a well reported issue, that I had hoped would be addressed by the 12.3.1 patch, but it appears it is not the case.

Can anyone adivse a solution? Would returning the monitorand replacing it with a Thundebolt monitor, a Benq PD2725U, help? That is is Thunderbolt betrer behaved? I am well aware of the bandwidth limitiations of usb c.

Thanks

Graeme

[Re-Titled by Moderator]

Mac mini, macOS 12.3

Posted on May 1, 2022 4:45 AM

Reply

Answer 1

Top-ranking reply

hcsitas

Level 6

12,734 points

May 1, 2022 9:01 AM in response to hcsitas

Apologies for the confusing response, you’re obviously in the right place.

+1 to @D.I. Johnson, adding

Disable Sleep, it’s unnecessary on later Macs, all pain, no gain. To disable, set your Energy Saver settings to as shown:

Separately, avoid manual sleep, use screen lock instead or let the display switch off/auto-lock on timer. For long or overnight absences, shut.

Reply

Answer 2

GForce_n1 Author

Level 1

5 points

May 5, 2022 4:07 PM in response to hcsitas

I think you are correct; the implementation of usb c on the mini just seems a bit strange. It struggles where pcs seem not to have any problems.

I have went with a hdmi + usb b connection for my mini and usb c for my windows laptop. Works with no issues, even with power save enabled. Keyboard is a wired apple keyboard and mouse a Logitech Triathlon mouse connected by dongle. The external puck control on the Benq and kvm switch makes the dual setup easy to use.

Reply

Answer 3

May 1, 2022 8:42 AM in response to GForce_n1

Very many others have reported similar issues with monitors refusing to wake fro sleep on the Mac mini.

A generally accepted workaround is to prevent the mini from sleeping. Apparently sleep is unnecessary for the M1 processor.

Visit System Preferences > Energy Saver and disable the option. Allow the screen to sleep, but disable the option for the computer itself.

Reply

Answer 4

GForce_n1 Author

Level 1

5 points

May 1, 2022 9:06 AM in response to hcsitas

That's useful.

Are things different with a Thunderbolt connection; I could exchage the screen for the more expensive Thunderbolt model (PD2725U)? I am quite pleased with the monitor, it even has a mac colour profile.

I have tried changing the displayport setting from 1.4 to 1.1 after reading this might help. I will report back.

Graeme

Reply

Answer 5

GForce_n1 Author

Level 1

5 points

May 1, 2022 11:04 AM in response to hcsitas

I understand, and yes this is probably fine. I was interested if there was a solution or a planned solution as it is a bit odd that the default setting will cause problems to anyone trying to use a usb c monitor.

Reply

Answer 6

GForce_n1 Author

Level 1

5 points

May 2, 2022 3:05 PM in response to hcsitas

It seems that just when I thought things were solved, they're not!

On powering on the monitor will display the desktop but the keyboard and mouse do not function. Removing and reinserting the usb c cable activites both! No such issues with my windows 10 laptop, so it seems to be related to the m1.

A pain in the neck given that I hope to share the keyboard, mouse and monitor between the two systems! Could this be a fault or is it a 'feature' of the m1?

Reply

Answer 7

hcsitas

Level 6

12,734 points

May 2, 2022 5:58 PM in response to GForce_n1

Direct USB-C to USB-C for monitor to Macs doesn’t work very well because monitors are clueless on what’s connected, a power-hungry laptop or power re-buffing desktop. I would connect the monitor’s USB C to the mini’s USB-A port using suitable C-A adapter/cable to enable hub functions. For video, connect HDMI-HDMI with a cable not longer than 5’, should fix.

Reply

Answer 8

hcsitas

Level 6

12,734 points

May 5, 2022 4:16 PM in response to GForce_n1

It’s not strange at all, it’s demanding, as it should be. Monitors have no business providing power over USB-C unless specifically requested. If they do, they need to be rebuffed, ignored or confused. The mini does them all😁

Reply