I have just recently noticed a oil smell while I'm stuck in traffic with my foot on the brake in D but when I put it in N it seems to go away. It seems to have started after i got the S Tronic box serviced. When I went to take of earlier the car also stuttered and i could hear a rattling sound. It's only done it the one time and I cant recreate it. I'm thinking it's something to do with leaking when under pressure while sitting with my foot on the brake in D and now the gearbox may be a bit low on oil. Has anyone came across this before? 

Hi I used to have the same problem, happened after the stronic oil change

apparantly (as this is what the garage said) an o ring (or something on the gearbox cooler) has snapped when retightening and there was a tiny oil leak when in D and not driving (something to do with pressure)

they changed it (cost £6 from Audi, again this is what they said - I didn’t pay they accepted they had messed it up...)

the smell to a while to disappear but it did eventually after a few month...

it could also be the DPF regen smell, or both...

get I checked by the garage where you had the oil change done... 

hope this helps