Sig:X ground noise when turning knobs, when guitar is not plugged in

Amps & Cabs
1

Hello,

I was recently playing my sig when is accidentally stumbled on an issue. When nothing is plugged into the input, when I touch the volume knob on the active channel, I get a loud 60 cycle hum. When I have my guitar plugged into the input, this does not happen.

Nothing is plugged into the effects loop. Power to the amp is well grounded.

Any thoughts?

2

Could be a dirty input jack that isn’t fully closing (shorting to ground) when unplugged.

Dave

3

Hmmmm. Interesting. What would be the best way to clean that? Q-tip and rubbing alcohol or deoxit or something?