An update: I have been spraying the insides of the pots with some contact cleaner (M.G. Chemicals brand Electrosolve). I haven't had a whole lot of time to play, but my issues seem to have diminished significantly. I did have a problem getting a proper amount of volume when I turned the amp on tonight, but that's not unusual; I tweak the volume pot, and after a loud and unpleasant pop, the level shoots right up. I have noticed that if I play before I fix my volume problem, it sounds like the speakers are perforated. This surely can't be the case, though, as after I fix the volume, it sounds perfectly fine.