VMs freeze up intermittently

Of late I’ve been noticing that at random times VMs (all based on Debian minimal) will just freeze up and go non-responsive.

For example: I created a VM to mount thumb drives to, it’s a named disposable. This morning I mounted a thumbdrive on it. Later on I went to mount a second thumbdrive to it, and it wouldn’t respond. I got a brief animation of something jumping up and down on my kde screen, but the drive didn’t mount; nor could I open a terminal to try to figure out what’s going wrong. I ended up having to restart the qube.

The only possible clue I have (since I can’t see what’s going on, on on the frozen qube), is that I found that putting a “export -f ” in a file in /etc/profile.d (so that it gets read when a shell is opened) would reliably cause the qube to be frozen. If I had a terminal window open, I could edit the file and remove the export statement, and it would work. However…this could be a totally different issue.

Any ideas on how I might try to debug this? There doesn’t seem to be a way to ssh into a qube but I cannot open a terminal on that qube when it decides to freeze up.