I have 3 guitars, a pedalboard going stereo out to two amps. With 2 of the guitars, the whole system runs beautifully. But when I use the other guitar plugged into the pedalboard, I get noise. Noise that I can stop when I touch the strings. Like a ground issue noise. Here's the kicker. When I plug that guitar straight into the amp it's dead silent. No noise. I thought maybe that guitar had higher output pickups than the other 2 and the pedalboard was picking up on it. But all my guitars have basically the same outputs. Single coil neck (Low output) Humbucker bridge (High input). Has anyone here experienced something like this? Thanks.