Hi gareth
2 auto electricians have checked it unfortunately the ecu wont store the fault.as it works when first starting after you enter the car but before driving off.and when the stop start kicks in but again as you drive off both 12v cigarette lighter and window stop working.
I have been told
Possible auto stop start prob
Loose connection
Something to do with voltage drop
Just seems to frustrating it was a auto electrician who said only audi could prob identify and fix it