So I built up a Mysterioso that Haberdasher etched me. I've found that a get a very fizzy sort of high frequency crackling that rides on top of the normal notes. It is only apparent when the boost is down. Very annoying. Anyways I was wondering if some others who have built this long retired PCB had this same issue. I am using it with the mids switch off and it happens in both buffered and bypass mode. Sounds very much like it could be a characteristic of the circuit itself.
Other than that though this thing sounds great. Super smooth overdrive that sustains forever. Really awesome sounding. I am just hoping that this crackle is user error :)