So, my amp is a Silvertone 1484 (Twin Twelve), love it. I am, however, amp-tech-ly ignorant, and have no idea how to really fix my own problems. Other day I turn it on, get massive amounts of noise and hum and clicking (the clicking vanishes when I turn of the tremolo). I check the preamp tubes, one seems to be microphonic. Two days later I turn it on again - some hum, more than usual, but no MASSIVE NOISE. Swap the possibly microphonic tube with a Sovtek 12ax7... hum increases dramatically (and unacceptably! Screw you, Sovtek!). Switch it with another, hum's back down... not fixed, but ok for now. Try switching out the tremolo tube... no real effect. Blue glow from one power tube (I'm currently running a 5881 and a Silvertone 6L6 in one of the more laughable slapped-together power tube arrangements ever - yes, I should change it, no, I haven't had a chance). Now I still have clicking from the tremolo, still have more hum than before things went wrong, and still have no clue what is going on. Help? Update: Tried it out again. A LOT of hissing and crackling and static, still has that hum going on. Augh.