I hadn't paid much attention to the hum I was getting until a seasoned player told me it should not be making that noise - the amp should be dead quiet when sitting there and not playing. Got a Mark lll red stripe head and 1 x 12 cab. Went through the manual and did all the tube switching to no avail - all the knobs can be turned right down but when the master is turned up and the reverb on back is turned up, you get some hiss but a fairly juicy 60 cycle hum. This is with no input plugged in, also tried with reverb unplugged - no diff. (also with an input) Could this be capacitor or is this this normal to have a hum when things cranked? Right now my babys scattered in pieces on the table and my other babys getting pissed cus its Christmas dinner soon....help...