N2 unresponsive after a long period of time

Hi, I’ve got 3 N2s running CE 9.2.1 in my house. I’ve had a couple instances where two of them have become unresponsive after long period (a month or two) of being idle. Unresponsive here means remote presses don’t move the cursor and I can’t see any media through Kodi’s webserver. My media is on a NAS with a shared Kodi database and other Windows based Kodi clients can still access the media properly. I can still ssh in to the N2s to reboot. The reboot takes 20-30seconds to initiate instead of what seems to be “an instant” normally.

Any thoughts on what might be causing this?

P.S. I don’t have logs, but will enable debug logging and hopefully catch something next time.