I have a Punch 300 mono for a single 10" sub. I've had it for a while but never installed it. I have the PLC2 installed in the console. The rest of the amplifier works very well and the light on the level control comes on and changes color; however, there is no change in the level when the knob is rotated. I'm well past the return period and don't want to waste another $30 if the circuit in the amp is bad.
Does anybody know how to troubleshoot without another unit of either available to swap?