With the radio on; turning-on the headlights, causes the radio to let-out a teriffic noise, then go off. the radio is dead as long as the head loghts are off.
Turning-off the head lights and turning-on the radio, the radio works, but has lost all of it’s presets. It acts as though the power was removed from the radio, much the same as a bettery cable disconnect.
Does anyone know where the “Power Amplifier” is located (connector?)?
No fuses are blown, battery cables are ok, and clean.
This is one of those hard to find things. I would start by making sure the dashboard has a good ground. Often it has a separate wire just for that. I am not suggesting that the ground IS the problem, only that it could be and it is easy, or at least cheap to check.