I have a used Orange Crush 30R which works and sounds great. However, I just got a footswitch for it and the footswitch's LED does light up when switching channels and if I plug the guitar into the high input and play low notes (e.g. the E and A string) I get this gross.....sound? Whenever I do that, the LED sort of lights up but only when the E and A are all crazy sounding. Does anyone know what the problem is and if it's fixable? Bad cable maybe? I've tried two different cables but maybe they're just of low quality? Thanks.