mechatronic control module has been replaced under warranty....
Do I take it that these are prone to failure then? or is it a regular serviceable unit?
Thanks for the replies!!
Prone to failure
and they are the thick end of £1000..........
Later units seem to be more reliable 
Have to correct you Rhys, its normally from 57 onwards that more are prone to earlier failure. Cars from 07 down are less likely.
Must be early Audi's that seem to suffer then

I've scanned 3-4 04 / 54 plates with failed mechatronics units

Glad I didn't go DSG this time around if it is the later units failing!