One problem related to front seat recliner has been reported for the 2000 Audi S4. The most recently reported issues are listed below.
Drivers seat is rocking. When you shift gears or brake you will feel the rocking motion. Its continuosly gotten worse over the past year. I've just taken it in to the dealer and they "could reproduce the problem & it is within specs. " I feel that this is getting worse and is even unsafe. I have spoke with many other owners about this and they have gotten the same response from the dealers.