Tried so far

Stripped out head unit checked rear fuse (OK) refitted unit - still no sound.

Checked MOST bus light in boot (trunk). Module behind amp (bluetooth?), this unit receives signal first, then amp then TV module. Disconnected and plugged all back in, no loose wires bad earths etc. - still no sound

Not sure if MOST bus goes to other units but I could not see any.

Advice, ideas on if other units still to be checked?

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