I picked up my new iPhone Bluetooth headset on Wednesday and have been having connectivity problems with it...or the iPhone itself...ever since. When the iPhone and the iPhone headset are paired, the audio "stutters" when the headset is out of line-of-sight with the iPhone. This happens even while playing with my dog in the park, so it's not an interference issue with other electronics. I tried pairing the iPhone with a Plantronics Bluetooth headset--same result. The Genius at my Apple Store easily duplicated the problem, and he figured it must be an issue with the iPhone itself, so he replaced it. I waited at the Store until my new iPhone activated, then the Genius and I tested it. Unfortunately, the problem remained. The Genius and I then paired the iPhone Bluetooth headset with two display iPhones in the Store--again, same result. Very frustrating. Anyone having any similar issues? Anyone know of a "fix"?