I noticed something weird with the volume knob on my JP7. When I turn the knob up, I get some kind of humming noise when the knob is about 60-80% turned up, but when the volume is turned up all the way the hum is gone. I don't think this is ground-related as touching the string does not have any effect on this humming noise. It also only appears on a distorted sound.
Apart from this the volume knob works just fine.
Does anybody have an idea what could be causing this? Could this be a faulty volume knob?
clean the pot with contact cleaner.