I traded away my old Dual Recto for a Mark I that seemed to work for a few weeks.
After a few weeks it suddenly developed a loud hum that occurs anytime the amp is on. It hums when no guitar is plugged in, when no effects are in the loop, when I try using a patch cable in the effects loop, and the only way to change the intensity of the hum is to raise or lower the master volume. No other control has any bearing on the hum, including reverb, presence, the EQ, volume 1 or volume 2.
I've tried swapping power and preamp tubes with no change. I have tried plugging it in to an external cabinet to no avail. I've tried different electrical outlets, and different venues and absolutely no change.
Occasionally the amp will turn on and run quiet and I've noticed the tone is substantially better. Then after a bit of time playing the hum will start and the tone becomes noticeably worse. It won't cut through in a band situation well, and it seems to lose the strong midrange punch and the breakup from the amp becomes harsh and non-musical.
I took a short video of what the map is doing that I'll post below. Thank you in advance for any help.
After a few weeks it suddenly developed a loud hum that occurs anytime the amp is on. It hums when no guitar is plugged in, when no effects are in the loop, when I try using a patch cable in the effects loop, and the only way to change the intensity of the hum is to raise or lower the master volume. No other control has any bearing on the hum, including reverb, presence, the EQ, volume 1 or volume 2.
I've tried swapping power and preamp tubes with no change. I have tried plugging it in to an external cabinet to no avail. I've tried different electrical outlets, and different venues and absolutely no change.
Occasionally the amp will turn on and run quiet and I've noticed the tone is substantially better. Then after a bit of time playing the hum will start and the tone becomes noticeably worse. It won't cut through in a band situation well, and it seems to lose the strong midrange punch and the breakup from the amp becomes harsh and non-musical.
I took a short video of what the map is doing that I'll post below. Thank you in advance for any help.