Nexus 4 Rattling

I have been using my nexus 4 for almost a week and I can hear something rattle whenever i set it down on the table or shake my phone really close to my ear or even flip it from the front to the back. I read somewhere else that is the camera autofocus. So I was wondering if I should call google for a replacement. I know the replacement could have other problems so I don't know if I want to do that.