Well, i had the common headlight switch problem, which basically meant my fogs came on if i turned the sidelights/dipped on. I managed with it for a few weeks as you could sort of turn it and push it and manage to get them to stay off. But got to a point where they wouldnt stay off yestarday, so decided to take it out and have a look. I got a quote from audi for 60 quid plus vat for a new unit - and couldnt find any on ebay, so i thought i mightaswel take it apart and see what happens. anyway i completely dismantled the switch, (undone a few clips lol) and removed all the excess grease in the rotating plastic section, (still loads left though) and reset it in its correct position (after trial and error), put it all backtogether and now works perfectly ! Not sure if it will just go back to being dodgy, but defo worth a try for people having the same problem.