when ever my wah pedal is decompressed (when pedal is about to turn off but has not been clicked yet) it begins to make a shhhh sound. I would leave it in that position and the sound would continue until I turn the pedal off, compress the pedal (move it away from the clicker), or play a note. I don't know if my pedal is suppose to be this way. Please let me know if there is something wrong