Princeton 68 Reissue input problem

Hello fellow Fenderites, wondering if anyone has had a problem with a 68 reissue Princeton, specifically inputs. Occasionally bad connection, have to jiggle it around, sometimes for awhile. It just started to sometime produce a loud static, sound like the roar of the surf (and I don't mean surf guitar). It starts when I plug in and try to get it going, will continue even with jack out, both inputs. Reacts to volume. Tried different cables to no avail. Comes and goes. Right now it's working so don't think it's tubes, though I'm no expert. Any insight anyone may have is appreciated.

That could be a dirty jack or tube socket, preamp tube or a resistor going. I recently repaired a Fender Excelsior that was making that kind of sound and it was a bad plate resistor.
I'd try cleaning the jack with DeoxIT first followed by cleaning the tube socket and trying a different preamp tube. If those don't help, see if the amp is under warranty before doing anything else.

Thanks for the response Don, I'll try the cleaning the sockets first. I did notice also that I was getting some static when I touched the power cord where it connects to the amp - could it possibly be a grounding issue? Also as the problem occurs with both inputs it seems it's either something like grounding or plate resistor. It's fine right now, but once it happens once (or twice), it's bound to happen again.