My new Mark V combo was only a few weeks old when I started having problems. Ch 1 sounded like crap. Ch2 was total distorstion and was popping. Ch 3 sounded too clean and was weak. I replaced one 12AX7 and Ch 1 sounded a lot better. Took it to the service repair shop because the other two channels were still real bad. Ends up I had a shorted JFET, a couple bad solder joints, needed two more 12AX7 and one of the wiring harnesses had to be rerouted because it was picking up noise. Amp sounds great now, but my Mark V head with 4x12 has it beat. Never had a problem the Mark V head and its a good thing had it so I could compare amps. In your mind you know it does not sound right but you always try to think its something you are doing wrong or something simple you can fix. Mark V is a great amp and I love it. I just got a lemon Mark V combo.
