Originally Posted by
45SET
1: Check all your interior panels to see if any are loose.
2: Do you have any aftermarket sound gear in the car (Subs, amps)? If so check these are tight.
3: The rear spoiler is meant to have a little bit of give... this is fine.
4: Check your rear number plate surround isn't loose. This can be tested by letting the car idle and standing behind the car. If it shakes on idle, it'll probably shake more while your driving the car.
5: If its none of the above, take a mechanic for a drive in the car, and get them to listen for it and see what they say. The DC5R has no sound deadening in it (Just has a couple of pieces of foam stuck to the underside of the carpet), so this might be normal road noise.