How to find out why my VM keeps getting randomly aborted?

Some time ago my VM (Win11 host, Rocky Linux 8 guest) started to randomly abort. Usually, I just minimize the window, do something else and then notice that it's gone. So far, I wasn't ever able to "catch" it in the act (i.e. when I'm actively interacting with VM) and VM doesn't do any tasks when it gets aborted (just some windows open).

I have 64GB RAM and I tied lowering VM RAM from 42GB to 32GB with no success. Also tried `VBoxInternal/RamPreAlloc 1` option in case it was OoM issue and that didn't help.

There is nothing in the logs either (they end with "resuming" event when I resume it then there is nothing for hours until the VM is aborted).

Not sure if the issue was caused by some VBox update but it wasn't a problem at the start. Currently I'm on 7.0.20 (I had to revert from 7.1 since that's a broken mess).

Any tips on how to diagnose it and fix it?