M2 Max Macbook Pro keeps waking up my displays at night on its own

[kasakka]

I have two Samsung G70A 28" 4K 144 Hz displays connected to my M2 Max Macbook Pro 16". The laptop itself is run with lid closed. One display is connected to the Mac's HDMI port, and the other via CableMatters USB-C to Displayport 1.4 adapter.

Unless I remove the power cable from my Mac, it will randomly keep turning the displays on, then back off. They don't show any image, just turn on and in a few seconds turn back off, then randomly do the same thing again.

If I connect the same display cables to my desktop PC, which is connected to the same power strip, zero issues. Removing one of the displays from the Mac makes no difference.

Removing any USB peripherals does not fix this behavior either. The only thing that seems to work is if I pull the power cable from the Mac.

It will often also immediately wake back up from sleep if I select Sleep from the Apple icon menu. I have to basically quickly take my hands off the keyboard and mouse for it to not do this. This does not seem to happen if it auto-sleeps, but the displays waking up problem does.

If I run:

log show |grep -i "Wake reason"

there are no wake reasons for e.g last night when it was doing this.

The logs have some "systemWokenByWiFi: System wake reason: <SMC.OutboxNotEmpty smc.70070000 wifibt bluetooth-pcie>, was not woken by WiFi" from previous days even though "Wake for network access" is set to "Never".

Has anyone seen anything like this?

 

[Fishrrman]

I don't have "a solution" to your problem.

Just a couple of "Fishrrman's usual dumb™" suggestions:
1. Why not just TURN OFF both displays at night, using the power buttons?
or...
2. Get a small power strip. Plug both displays into it. At night, just reach down and turn OFF the power strip (knocking off both displays). In the morning, turn it back on.

 

[LAHegarty]

Never,

And Never.

 

[kasakka]

Never,

View attachment 2413863

And Never.

View attachment 2413865

Both are set on Never.

 

[kasakka]

I don't have "a solution" to your problem.

Just a couple of "Fishrrman's usual dumb™" suggestions:
1. Why not just TURN OFF both displays at night, using the power buttons?
or...
2. Get a small power strip. Plug both displays into it. At night, just reach down and turn OFF the power strip (knocking off both displays). In the morning, turn it back on.

This is what I do but it's a bit inconvenient to turn off the displays as it is not a one click operation. I'd rather find the root cause.