Yesterday I spent two hours twiquing my BYOC wah to try and get the sweep to sound just right. I finally got it, but now it makes my amp fart whenever it's in the heal-down (bass) position. Is there a way to reduce this without affecting the sweep too much?
It's the amp, the cab can't take the bass. You could try lowering the bass on your amp.
turn the reverb down>>
The fart is probably the speaker on your amp. Sounds like it could be loose or damaged (something that could of been occurring but amplified by the Wah). Try to lower your bass on the amp to see if it makes a difference.