I actually did this just now. And it's 100% near the camera/power, but I just cant check what exactly is the culprit because the power button is heavily build in into (I don't want to risk voiding my warranty), and the camera I can take out, but I'm afraid to reassemble the phone and power it on with/out it.
I tried holding the power tightly when the screen was lifted, and the noise was lesser, but still there. When I gripped the camera module tightly, the noise was pretty much gone. I think that my grip on the camera damped the vibrations from the vibrator motor. But it wasn't from the fact that the module rattles, it is most probably that something (lenses?) IN the camera module rattles.
If so, this is unfixable, apart from removing your camera module :(