hey guys ive noticed something about my iphone 4S. when i tap on the back in the the corner with the camera (from the apple logo to the actual corner) i hear a rattling sound. this happens even with the slightest tap and even though its not a big deal i feel like it shouldn't do that. it also kinda makes the phone feel cheap. oh, and its not because a button is loose like i original thought. anyone else notice this?