Boss Super Feedbacker & Distortion DF-2 Problem

[Stevenrb718]

Hi. I have a Boss DF-2 that has a weird problem. Everything works properly, but when I go to hold the pedal down for feedback, it does an oscillating warble sound rather than the feedback.  What piece is faulty?

[blackieNYC]

It's fake feedback, with a little vibrato added in. I think it's actually kind of cool. From what you are saying, it might be working properly.  It generates an oscillator, which will be a harmonic of the note you play when you hit the switch. One of the knobs controls the "feedback frequency", generating a fifth, or third, or whatever, based on the position of this knob.  Play a note and hold the stomp switch down. Maybe you get a fifth.  Now release, reposition the feedback control, play the same note, and you should get some other harmonic. What does the knob do?