This Aria Loco bass combo 6126B is making plenty of output, but also unwanted noises as follows. With the volume at zero, moving the bass eq produces a growliing noise at full volume. Moving the mid controls makes an equally loud squawking sound and the treble makes a horrendous shriek.
Tapping the boards has no effect. Not sure I will be able to find the circuit for this one, so any pointers please before I let my "phantom" fingers loose on it?
Steve.