Last December I bought an MGFX30 amp. After a few months of use I realized that the volume knob does not correctly work. On either of the 4 channels if I turn the volume fully down, and then turn it up, the volume becomes faint and distant. If I then switch to any other channel without touching the volume knob, the volume of the other channel is correct, loud and clear.
I returned the amp to the seller and it got replaced today to a brand new one. When I started to use it today, I immediately checked it, and have the same issue: the volume being turned fully down then up - sound is faint and distant, but other channels produce a loud, clear sound.
I don't think that this is the way the amp should work. However, the odds of having two faulty models from the same seller seems to be very low.
How can I fix this issue? Is this the way the volume knob supposed to work?
Just change the volume knob. Not hard. I just changed one in a old valve fx rack mount.