Bose Bluetooth 2 (BT2) Pairing Issue with iOS 5.1
Users of the Bose BT2 headset will need to download and install firmware verison 1.05 to correct the pairing issue that effects the iPhone 4S (and possibly other models) that have been upgraded to iOS 5.1.
The firmware can be located on Bose's website at http://worldwide.bose.com/downloads/en/web/bose_bluetooth_system_overview/page.h tml
Once the firmware is downloaded, installed and then the headset is repaired with your phone, the connection issue should be fixed.
Common symptons (as I have experienced) are:
1. headset will randomly unpair and then repair itself with the handset even during a call
2. headset may only be partially paired with the phone, allowing the headset controls to function but will require that actual conversations will need to be done via the phone
3. Headset will periodically lose connectivity with the handset requiring that the headset be shut off then back on again
Apparently Blutooth upgrades in iOS 5.1 (support for v 3.0 +) causes problems with firmware 1.03 or older.
iPhone 4S, iOS 5.1, Bluetooth Pairing and Connection