Sure could use a hand, and I can't find what I'm looking for with the search. My 70's Fender Deluxe Reverb has an extremely sensitive reverb, in that when I walk in the room or even touch the amp a bit, my reverb gets all splashy and noisy. I'm thinking it's a microphonic tube, but I can't figure out which one to change. If I'm looking at the amp from the back, which one of the tubes should I change out to see if that's the problem? Thanks for any help.