I have fitted a switch to the amp remote line and no amount of swithing on and off of this switch, with suitable pauses between each operation, recovers the sound.

However the fault has developed now in that it is more frequent, it is happening in radio mode, rebooting via the hijack menu will not fix it, and I get more short noise and silence that continual noise.

I am thinking that the cars amp is OK and that my problem lies with my empeg(?).