Strange noise from new C30 :(

[Reedgm]

Hi,

I very recently purchased a 2010 Volvo c30 1.6 petrol, after the head gasket went on my 2006 235,000 mile V50, and I decided it wasn't worth fixing.

I like the C30 and it drives nicely, but there are a couple of weird noised I have noticed since picking it up. The strangest of which is a kind of rattle sound that can be heard when letting off the accelerator. At first I thought someone had fitted one of those fake turbo blow off valves, as that is how I would describe it sounding from the drivers seat, so it didn't worry me as I figured i'd just remove it. Although on further inspection it sounds more like a rattle.

It happens any time the car is given throttle and then released, whether the clutch is pressed or not pressed, in gear on not in gear, driving or not moving

I have put a video on Youtube;

https://youtu.be/51XyXVDeou4

Any help would be absolutely amazing! As these things tend to worry me