I recently bought a BH-905 as a Bluetooth headset for my iPhone 4 (iOS 5.0.1) and to my dismay it has a problem that has plagued that particular combination since iOS 4.3. Audio problem BH-905 It moves the balance over to the left ear, even moving the balance in settings doesn't do the trick. Repairing Bluetooth may fix it for a moment but it eventually starts playing out the left side. It's not a BH-905 issue as the headset works great on OSX Lion and phones that are not iOS based. It works fine in the wired mode, it's Bluetooth that's the problem. Something to do with how iOS sees the headset profile. My BH-503 really nice headset minus noise reduction doesn't have this problem. I hope Apple will fix the A2DP stack in an upcoming iOS update.