I just noticed it today, and I figure it must be the camera lens or something, but I want to know if it is normal. Nothing happens when i shake my phone, but when I tap it on the backside on the flash or under/on the camera lense it makes a noise as if something is loose in the phone. I first noticed it when I set the phone down and I am curious if anyone else has the same thing going on or knows as to why it would be doing this. I'm sure it is nothing major