OK, getting a bit concerned! Started car the other morning ( R56cooper) and she seemed to be really noisy. Noise is like a rattle when stationary. When on the move, sometimes feels like there's a flat spot around 2000rpm Also noticed when stationary, if pressing the throttle slightly to around 1500rpm, then backing off slightly and pressing pedal again, its like she misses slightly? On the move, accelerating the engine sounds kinda rattly, bassy and rough.

She still goes like stink, but deffo something not right

Timing chain/guides etc all changed less than 10 thousand miles ago, as she had this same rattle then only not as loud. Changing the chain etc didn't cure it, but now its a lot more noticeable. No engine smokeor anythong like that. Any ideas?