i love these pedals but they have alot of potential quality issues, cheap plastic jacks that are soldered to the circuit board, delicate and flimsy circuit traces, cheap potentiometers alot can happen to these especially if its put thru “rugged” use. once i learned enough about circuits and these units i have replaced the jacks, pots, wiring and switch (3pdt to make it true bypass)

also recommend running a circuit trace, start if you have signal at the 2nd lug of the volume pot (thus is the circuit output) then check the transistors and the jack (not as likely if you hear it actually switching, but could have a bad solder point to one its lugs)