PV XXX channel sw problem

[ruthuxter]

I'm trying to repair this xxx. When the clean channel is selected, both the clean and ultra leds come on, but there is no signal passed. I noticed also, when in crunch mode, the amp switches quickly from crunch to ultra and back, at power-up and power-off. Any suggestions for this repair would be greatly appreciated.

Thanks

[Jazz P Bass]

Peavey XXX

Is the amp acting up with the footswitch.
How does it work with the footswitch disconnected?
Call Peavey and ask for a schematic.
If you still have problems, post the scheme.