Thanks Thermionic. I have a Duel Caliber DC3 Mesa Boogie. I think it is around five years old. I will try cleaning the effects loop jack. Before I clean it should I be able to get it to crackle/pop or cut out by wiggling it when I plug something into it? Thanks for describing the strum method for discharging the filter caps. That sounds easy! I suppose with my luck the only way I will know if this doesn't work will be when I am in the middle of a performance. Thanks again John