I have a problem with static in the potentiometer knob on my PA2V2. I can only hear it while I'm turning it up or down. I emailed Gary, and this is the response he gave me, in case anyone else has encountered this same problem.
I recently received the amp, as you know, and I have a question. Is it normal to hear static while turning the potentiometer knob up/down? It seems like in certain songs it does, and certain ones it doesn't. But even when it does do it, I can turn the knob up and down really fast, then it disappears. Any feedback?
This static noise is a consequence of my design, which actually keeps the potentiometer out of the audio signal path. If I put the potentiometer into the audio signal path then the scratching noise would go away. However, the bad part about this is that the audio signal would technically be degraded for the entire time that music was playing. I thought it would be best to have the amp make a little noise only when the knob is turned, but to have the best sound when the knob was set. The resistive path in these potentiometers isn't as pure as in a regular resistor.
Hope this helps out.