i just got this pedal second hand..it works but when i pluck a string its makes a sound but then keeps getting louder until i mute the strings, it does this on all strings..sound like maybe something isnt grounded. maybe i need a new instrument cable.. i pluck the strings and it keeps getting louder with volume or distorion or it peaks, im not sure how to describe but somthings wrong..i tried fiddling on the amp and the pedal.. any sugestions, thanks

it does the same now when i plug into line 6 gearbox, maybe its because im using an acoustic electric, i think turning down the volume all the way down on the guitar helps. that could be it.

Feedback ? Happens to my semi hollow jazz guitar too, even with no effect if I sit too close to the speaker.

ya i guess it was feedback, thanks it seems to help to keep the guitar far enough away from the amp.