Has anyone else here had issues with this or know what might cause it? I have built it off the attached schematic.
However, on my breadboard all I get is a whine that vaguely interacts with the guitar but completely overpowers it. It does a bunch of weird things like stops making sound when I play certain notes on the guitar and then starting up again when I play certain other. I can't figure out what is causing it though. Would it be possible that stray breadboard capacitance is allowing it to oscilate by sending the output back to the input? The two pins are quite close. I've tried using small caps to filter the power rails but that had no effect.