In reply to:
Turning the volume up and down also produces quick pops when you first touch the control (not a knob, just a couple of buttons). He says the pots may need cleaning...?
Waitaminute... try touching any other metal unpainted part of the case (back plate maybe?) and see if you get the same popping. If I understand correctly, it has a volume up and a volume down button, not a sweep pot (volume knob)?
If the popping still occurs (don't touch it for a few mins, then touch a metal part and see if it happens) then you've got a chassis ground problem.
Bren R.
