[unintelligible]

That's quite the odd noise. Do you know what steps they took to diagnose it? It seems odd that the dealer would just say they can't figure out what's wrong and leave it at that. My response would be... "try harder." If they admitted it's not normal and it's under warranty they need to fix it - all the way up to replacing the entire motor if that's necessary.

And I would have the same concerns about just waiting it out... how long is your warranty good for? If it's is same as in the US, warranty is over at 60k, so if you're at 55k, you don't have much time left. I'd want it fixed pronto.