Distortion Plus Oscillation problems..help needed

[MadMatt]

what to do when my dist+ clone that sounds great when engaged, starts to oscillate after stomping it to true bypass?
any help more than welcome!

[GREEN FUZ]

First thing I`d do in this case is check the switch wiring.

[soulsonic]

What style of true bypass wiring did you use? I recommend the style that grounds the input of the effect circuit when it's bypassed - if you didn't use that kind it may be oscillating because the effect circuit input is open, and with no signal going to it, it's just "doing it's own thing", ie; oscillating. When you use the grounding style of true bypass switch, the effect circuit is muted so this won't happen.