Restarts aren't necessary?

[xZork]

I didn't think so, but one of my jala's just quit on me and required a restart (unplug for a few seconds.) The bad part is I missed out on a few shifts before I woke up. Anyway, is this a freak occurrence or what? CGMiner didn't show zombie status, it was locked up also. I was running solid for 10 days, since I last restarted messing around. What could be the problem? Soft or hard?

Temp is only 48c so it isn't heat.

Thanks for any input.

Edit:

This jala hasn't gave me to much problem, but it does run the hottest. It hashes @ 8.9-9.2 all day long. It was pushing 68c so I took the cover off and flipped the fan, now 48 is the hot point.

[vpasic]

these kind of things occurred occasionally.
once a month I have exact same problem with my 3x60GH units.
I just close and fire up cgminer and everything continue to work like nothing happened.