What the seller had to say:
“Unfortunately, while it passes audio when bypassed, the pedal makes no sound
when engaged – neither affected nor unaffected. The LED comes on so something
is still connected as I tested it with a battery and an adapter.”
“I’ve
included a “gut shot” [see Disqus]. The black “goo” you see is something WMD and some other
boutique pedal makers do to keep others from copying their circuits. This might be an easy fix for someone who knows
about the inner workings of pedals (I don’t).”
