Well, after 2 years with no real probs to talk of, its my turn to have something wrong (though it still hasnt hit 50k yet!). On returning home after a long journey last night, I noticed a strange knocking noise coming from the back of the car at very slow speeds, ie, when starting to pull away or almost coming to a stop. Its too quiet to be a wheel bearing and dont think its anything to do with the brakes. It literally just sounds like someone tapping the back of the car which increases with speed! Theres no vibration and it doesnt appear to come from a particular corner. The noise dissapears when the car gets properly moving, though that could be the engine drowning it out!
A brief inspection of the arches showed nothing abnormal, and there is no-one tied up in the boot... Any ideas?