I had my car in for "timing belt" "waterpump" "dsg oil change" plus an m.o.t, they told me i was due for a service (refresh) on my air con, I said not just now no cash left :( . Got my car back and all seemed fine,but put my air con on later that day and it now seems very noisey and it gets louder when I accelerate ? did not sound like this before it went to VW (main dealer) have called them and it's booked back in on Thursday. Any ideas on what's happened ?