I get that at the office whenever my cloud backup is running, so I always figured that was the cause....., but then yesterday I got it here at home for a loong time and I had NOTHING running in the background, so I dunno what the real problem is.

Sometimes a reboot of the computer gives you a reprieve for a day or two, but if you're shutting the system down on a regular basis, this probably wont help.

Its some kind of resource management issue within the PS program, I dont think its anything we can "fix".