Help! tell me whats wrong . When I plug in and play, quite often (not all the time), the dB level is initially not as loud as it should be. Id say the volume/dB level is only about 65-70% what it should be. After about 10 mins, the dB level will increase instantaneously. Ive found that volume levels will come up if I toggle the bright boost switch on the pre-amp. I can position the switch back and the levels will stay up. This does not work when I toggle the low boost switch or the ground switch in the back. Occasionally, the level will drop back down again after about 10-15 mins of playing but not so often when the amp is warmed up. Obviously this is annoying, especially at a gig in the middle of the first set. I opened the unit up and checked for loose connections, inspected the tubes, etc. I really dont think its a tube issue cause the tubes looked ok and I swapped the two 12AX7s in case the one was causing the problem but I still get the same thing. I noticed there is a small capacitor in the bright boost switch circuit. Im thinking it might be this cap ?? What do you think?