No sounds

[brucemillar]

Folks

I have searched and searched with no luck.

I have just purchased a 4.8is with factory Nav (MKIV) and radio + CD changer in boot and tape behind Nav screen. No phone or TV - all stock.

I have no sound from any devices, including the nav.

The orange light comes on with the radio on/off button and I can display radio, CD, Nav etc.

I have upgraded to V32 OS - No change
Removed the radio in the boot for 30 minutes
Removed the head unit for 30 minutes
Disconnected the battery for 1 hour - No change
Fitted new battery (old one was duff)
Pulled all the fuses 7, etc in the glove box and boot - No change
Pushed the RT button on the steering wheel - I have no phone module.

I do get a warning beep from the parking sensors. Nothing from anything else.

To me it is like we are stuck on mute? Any clues before I send it away for repair?