So I've noticed this problem with my Mark IV ever since I've owned it (a year and a half approximately) where it warms up like a normal tube amp but for another 10 minutes it will hiss and pop (once or twice every 2 to 3 seconds) and the guitar sound would be pretty crappy (low gain, super compressed and solid state sounding with ratty distortion) sounding. After a bit, the popping would lessen and the guitar would sound better and better until everything seemed normal. I played it like this for about a year and did plenty of shows and lots of practices with it and experienced the same weird warm up deal and just learned to live with it.
Recently I moved back home and due to my crazy schedule, it has sat for three weeks) Today I tried playing through it and it never fully heated up. It just sat there sputtering and popping at me with VERY low guitar output.
I swapped all the tubes (pre and power), cleaned tube sockets, and even worked in a few switches that change the power amp circuitry (pentode/triode, class A/Simul, Standby, etc.) just moving them back and forth to work out any possible dust in there. No dice.
So has anyone had this issue and have an answer or at least a clever guess?
Recently I moved back home and due to my crazy schedule, it has sat for three weeks) Today I tried playing through it and it never fully heated up. It just sat there sputtering and popping at me with VERY low guitar output.
I swapped all the tubes (pre and power), cleaned tube sockets, and even worked in a few switches that change the power amp circuitry (pentode/triode, class A/Simul, Standby, etc.) just moving them back and forth to work out any possible dust in there. No dice.
So has anyone had this issue and have an answer or at least a clever guess?
