Well, I tried 2 different guitars, and it was still there for both, neither stronger nor weaker for either. Since it's basically only noticable on the dirty channel (which has beccame increasingly more noisy) I even tried changint out the tube in V2, but that didn't do anything at all. Ground switch also did nothing. Taking out all pedals also did nothing. So, I'm lead to believe that it's a bad power source. That's the one thing I didn't try yesterday, but I will try going to a different outlet this evening. Aside from all that, the amp has never sounded better :rolleyes: