A8parts do have a couple in.. though IIRC this is a part that can cause CP to trip, but at least you'd know everything works until you got to a dealer to remove it.

If you suspect a component, like the tuner, if you take apart the fibre connections and repatch it to bypass that device, the rest of the system should boot up. It's not that the car needs the tuner, but if that has failed, it breaks the fibre optic data loop....

Audi do have an official optical bypass connector which allows you to remove a device and plug the loop to keep it working, not sure if it would be available to non-trade though..

well the system works again now as normal no problems no idea what was up with it but there was water in the radio reciver, i did a loop on the fiber optic using my home cinema fiberoptic for the dolby 7.1 and it booted up

re-instated the box in the boot and its all working again

very strange
but will have to look into why my voice control is not there maybe i can buy the expantion only and slot it into my tuner ?

Same sort of process you use with computers and one I was about to suggest:
Disconnect/bypass everything you can and try a "minimal boot", then add things back in one by one until it fails.

Often, as you've discovered, it all works again. And if you're really lucky for a long while.

Could be some of the water had splashed up and was causing a short. Glad to hear you're back in business though.

SDS modules are available seperately, so you should be able to get hold of one.

yes i just hope it dose not break again i already have tax this month for the car and tyres next month and i dont want to fork out for new modules if they fail, its not until you have a D3 you realize just how reliant the car is on its electrical system its epic and if one component dies its game over they are not a very diy oriented car like the D2 was +++