Scratchy pot how to hunt down DC voltage?

[gbono]

Hard to say what's causing the poping/gain change issue? Though it sounds like you appear to have isolated it to the PA board. Did you replace the output transistors? Probably should move this to the Sunn section of this forum???

[Enzo]

Nah, don't move it, then there will be an Acoustic thread in the Sunn forum. Just start a new thread or split this off.

[distorto]

Yeah, I'm going to poke around and I'll start another thread in the Sunn section if I get stuck.