So I'm on my 3rd iPhone 5S replacement now. My first iPhone 5S had terrible battery life, so after troubleshooting with Apple they replaced it for me. My second iPhone 5S battery seemed to have improved, but every time the phone would vibrate it would make this horrible rattle snake noise, like something was coming apart internally. This never happened to my first one. Tapping the phone would also cause this vibration, and I tend to tap my phone gently whilst waiting for apps to load etc, hence why I noticed it. I did some research and found out that there are loose parts in the camera to allow it to autofocus. When I shook the phone gently the home button didn't rattle, but shaking it harder the camera lens would rattle, quite loudly too, a kind of deep rattle. I tested this on my old iPhone 4 and my iPad Mini, and when shaken very hardly I could barely hear any rattling noise from the auto-focus parts of the camera, and throughout the time I had used both devices I had never noticed a rattle. Now, if the phone didn't vibrate like it did, i'd be very happy with it, but it would drive me crazy every day with normal day to day use. Again, i took it to the apple store feeling bad for such a silly thing, even though there wasn't really anything wrong with the phone. The genius, was clearly not happy about it, did replace the phone for me out of good will but he said theres no guarantee the next one is going to be any better. I was very grateful and expressed I wasn't trying to be neurotic about it but the fact none of my devices did it was obviously enough for him to warrant a replacement. I took my 2nd replacement device home, I didn't check for any rattling, I just wanted to use the phone and enjoy it and hope It wouldn't have these minor issues. Unfortunately, when the phone went off it started rattling like a rattlesnake, same noise as before, but this time the home button AS WELL as the camera lens are rattling. Shaking the phone REALLY gently causes the home button to rattle, and shaking it with more force causes it to make the camera lens rattle in the same deep sounding rattle as the previous device. I just tested my old iPhone 4 out and shook it with even more force and I can barely hear the camera rattling. It is certainly worse than my previous device. This time I called up Apple, long story short after chatting with some very nice representatives, they are going to replace my device again, but said theres still no guarantee that the next one won't vibrate. I tried asking for a new sealed device if it would be possible to see if it would help resolve the issue, but the guy said he couldn't do that, which is fair enough I suppose. I even asked if it were possible for a different colour, which he couldn't do either. None the less, as long as the next one doesn't have this stupid rattle snake vibration, I'll be very happy. Im not going to be sitting there shaking my phone all day, I just want one that doesn't sound like the screws are falling apart, my first 5s and my old iPhone 4 never did that, and whilst I can understand every device is a little different they shouldn't have home buttons rattling at all, period. The camera rattling SLIGHTLY, i can understand, but nothing else should.