I was fitting anther unit into a car (wiring the docking sled) copying the wires from my car! I realized there was a cable extension on my unit which I thought was unnecessary, so I removed it to allow for more space to push unit back into place, but unfortunately in the extension cable wires are rerouted to different locations in the jack plug, didn’t notice this! plugged my unit back in and smelt electrical smoke quickly unplugged unit, notice the wires were crossed now because the extension cable was not in, replugged extension back in, unit still boots up ok and all functions are working probably , but there is a loud interference noise coming though all speakers in the car ! Tried the other empeg unit, which sounds clear... I think myself I have blown a noise suppresser inside the unit!! But I am no electrician!! cheers...