Yesterday I went to the Apple Store because I was constantly missing calls on my iPhone and the Genius ran an evaluation on my phone and determined that my antenna was faulty and replaced my iPhone. This new iPhone seems to be of even better quality than the one it replaced (no gap between the metal rim and the screen, etc.), but there is one problem with it, and for me it's a pretty big problem. I always like to keep my phone in silent mode with the alert set to vibrate, but with this iPhone I can barely feel, or let alone hear, the vibration. So far I've missed 4 calls since yesterday while the phone was sitting right next to me because I didn't hear it vibrating. Is there any way to increase the vibration intensity? Otherwise what can I do? I suppose that I could take the phone back and ask for another one, but if there's another solution I'd like to try that first. Any ideas?