Update:

No error codes on VAG COM

On the ramp the noise appears to be coming from the bellhousing area, the mech said "if it was a manual I'd have sworn it was a noisy thrust bearing". Obviously thats not an option here...

Anyway the garage owner has a friend who is a long time Audi mechanic and knows these cars and has offered to have a listen to it tonight.

So hopefully I'll have some news tomorrow.