I know this is a pretty old thread but I just wanted to say that I breadboarded the schematic on page one, took a few tries to get it to fire up and when it did, holy did it ever, honestly, with that schematic, no issues at all, no funky noises, the only thing I really did was take the ground off the pregain lug and now it doesn't shut off when rolled all the way back, resistor still works if its really needed to have that lug going to ground.
This circuit is loud!!! Thank you for sharing that schematic! Im messing around with tone stacks and the rat one sounds pretty good!