My engine's started making metallic scratching-type noises when if i lift off sharply. (At least i think its my engine as it goes away when i dip the clutch so i don't think its transmission). The oil level's fine and its only done ~30k miles so is this something to worry about or am i just getting paranoid?

 

If it goes away when you dip the clutch it sounds like the clutch release bearing, Nothing really to worry about as long as it doesn't fall apart. Is the car under warranty ? if so take it back & let them have a listen

Dean

 

Propshaft support bearing come loose?
You'll find it midway under car. If very loose it will touch the mid pipe and make a nasty noise. Could also be a loose heat shield on exhaust in various places.

Nick

 

As above, check the heat shields. Mine has done this a couple of times. Worrying metallic buzzing noise when you lift off for a gear change? Had one of mine tightned twice and another welded up because it cracked Hope it's nothing more sinister