I've searched and searched, and can't find the problem. I only have a volume loss in the effects loop when i'm running my Boss dd-20 in it. All the other pedals work fine. I switched the DD20 to "+4db" and still have a problem. I've replaced all the tubes, and the only thing I can think of now is the power supply. But the pedal turns on a works, just a HUGE volume loss even when it's not engaged. What's going on with it? I"m using a one spot to power it