okay, ive had this problem for a while now, but it was never so severe. whenever i use my grunge pedal, or whenever i unplug the ac power from the pedal itself, after i plug it back in, when i stomp it to turn on the distortion, it seems like it has to "warm up" kind of like a tube amp, but it takes a loooong time to get to full power. any specs that are needed about my setup, i will post.
Ever thought about getting it fixed? Posibaly using the 6 year warenty that came with it?
have u tried using a battery with it? Idk much about electronics, but that might help some of the other UGers help u out.