I bought a VOX V847 wah off the bay that has a fulltone inductor installed. When I engage the wah it works and sounds good, however, the wah effect will go out and the pedal just sounds kinda like a vol pedal. This scenerio goes back and forth, any suggestions on what could be the problem? The person I bought the pedal from said a local guy did the mod for him and it was working fine when he shipped it, maybe somehting got shaken up during shipping, sure. I want something reliable when I want to use it and this is pissing me off.