In my 1.9 TDI avant when i apply the brakes, 3/5 of the time there is a loud metallic click or clunk sound coming from what sound like the front end somewhere. (The noise i can only compare to like when you change gear on a pushbike, the chain clunk into the next cog, only louder). It doesnt seem to affect what the brakes are doing but the sound isnt right at all. Any ideas what this could be folks??