Rat noise chopping sound

[preciousmolina666]

I've built a rat distortion, everything is fine when the gain is at 12 o'clock, but when I try to turn the gain knob max, the sounds chops, if I strum after 2 sec the sound chops/stutter

[GGBB]

This is not unheard of. The opamp can experience lock up at high gain, and the JFET bias can oscillate around cutoff - both of which could produce results similar to your clip (I'd suspect cutoff before lockup). Any circuit variances from original? Check the bias on the JFET.