Is your seat belt holder on the middle door pillar wearing away? Where the belt rubs against the left hand corner of the hole, the plastic is being worn away. My father's A4 has over 40k miles on it, and hardly any wear can be seen. Perhaps it's because in a 3dr car you sit further away from the pillar, so there is more force on the holder. But still, in another 40k miles it would have warn through to the edge! I'm a bit lanky, so thought it may be set too low for me. But no, it's just the same at the highest setting.