My iMac freezes but audio keeps playing

[thefriendshipmachine]

It seems to happen randomly once a day.

The entire screen freezes and I can't move my mouse, but audio keeps playing. It's like the mac is still running but the screen is completely frozen.

Does anyone have any suggestions for help?

iMac (Retina 5K, 27-inch, 2019)
Radeon Pro Vega 48 8 GB
3.6 GHz 8-Core Intel Core i9

 

[eugenios]

It has happened also with mine. With BS 11.1 the lag was at max one sec and it was related to bluetooth. With BS 11.2 it happened one time only and the lag-freeze was about 15-20sec.

I have the same configuration as you.

 

[Coheebuzz]

Same here on M1, as you noticed already it's your screen freezing and not your Mac, you would be able to regain control if your monitor could be turned off and on. Which software were you running when it happened?