Hi Mstv , thanks so much for sharing your experience which has at least given me a little hope that I won't have to get rid of the car . I will try again the lowered seat suggestion and I have played with lumbar support but mainly just to adjust it so I couldn't feel it at all but I will try that too. I do live near a motorway so that is an option and your final suggestion is the best as that will indicate whether it is A6 in general or just mine but I can't help thinking it is unlikely my seat is wrongly installed but you never know. The part of this story that really confuses me is, as I said that I have driven my old A4 for years and another A3 for hundreds of miles all over europe with np problem at all , is it really possible that Audi dropped the ball with a car of this quality and price ? Thanks.