M2 Mac mini not sleeping...

[kattam]

Display is not off... the screen is not lit, but the display is not actually off.
It is in a power-down mode of some kind, similar as your Mac, sleep or standby, whatever.
As your Mac is sleeping, the display would need to be in a mode that allows a quick power up when you press a key, or whatever method you use to wake up your Mac.
The point I was trying to suggest was that the display may be on a different power scheme, depending on the computer that is in use.
I am curious, however... If you sleep your Mac, and note that the display's fan continues to run--then return to the computer later (maybe 30 minutes, or an hour), while the computer is still sleeping. Listen for the fan (don't touch anything, just listen for the fan). Is the fan still running after that time period? If the fan has shut itself off, then that's just how it works in standby mode when connected to a desktop Mac, and continues to a low power mode (fan off) more quickly on a laptop.
I guess that the difference is when there is a rechargeable battery in the power chain. The external display would likely power down more quickly (so no fan in sleep)
I don't know, I'm just guessing about this - Ask a "genius" at an Apple store, maybe you will get lucky and talk to someone that knows the right answer.

I've been checking the Display's fans now and then and to my knowledge they just keep running and never power down with my mac mini. I will try getting an answer from Apple support. Thanks!

 

[DeltaMac]

I would be interested in knowing what you find out.

 

[kattam]

I would be interested in knowing what you find out.

So far nothing much. Apple Support couldn't help me with this. Their guess is that the mac mini seems to be the issue and constantly waking the ASD in the background although the display stays off.

I've installed iStat and had a look at the activities. There was a peak at 4:38 in the night. Tracing back to the console I saw this log at the said time and it refers to some kind of syncing with the Address Book.

Address Book event completed. Changes: 0 (0/0/0). com.apple.message.domain: com.apple.sleepservices.addressbookData

According to iStat there is some sleeping done

It's also a lot of stuff like this:

com.apple.message.domain: com.apple.sleepwake.type com.apple.message.signature: Deep Idle com.apple.message.signature2: Maintenance Sleep com.apple.message.result: pass com.apple.message.summarize: YES

com.apple.message.domain: com.apple.sleepwake.waketime com.apple.message.waketime: 1277.437875 com.apple.message.waketype: Dark Wake from Deep Idle

Most of the time it's Mail and Contacts syncing or doing something in the background. Sometimes it's Dropbox but less frequently.

 

[kattam]

Me again. After scrolling through the log I've tried a couple of things.

Quitting Apple Mail before putting my mac mini to sleep.
Quitting Dropbox because this also caused wake ups.
Disabling messages in iCloud. I had this activated because I needed to download messages from my iPhone to my Mac. Usually in the past I didn't have this enabled.

Result:
None. Still waking up, bahahaha.