Garage that has car stripped to check valve timing... Top tensioner knackered - pump timing slipped... Appears that there's no damage amazingly enough it sounds fine on all 4 while cranking - not that we'll be doing that again without a new belt...
For reference, the belt was taut on the cam sprocket when the top cover was pulled back. E.
PS: This got a complete kit, incl waterpump & tensioner/guides 44K ago(with OE VAG) - why the premature failure?