I got a new replacement Centro two weeks ago, however the vibration is loud, and it actually disrupts my meetings. On my previous Centro, you would not hear when it vibrates, but this one, it vibrates with a rattle. I put paper in the back cover, however that did not solve anything. I think it might be the silver part is vibrating and rattling. When I squeeze the silver part, it gives a little squeak. Has any one else ever experienced this? Should I take it back to sprint and have them exchange it for another one?