When updated my iPhone 4 to ios6, this occurred on both my e53 X5 and e71 X6. I contacted Apple and was advised that somtimes there are errors in the sofware updated and a complete reset of the phone will resolve it. I did the complete reset (will have to re-pair all bluetooth and wifi connections following) and that resolved the issue. I have since gotten an iPhone 5 and have had no problems with pairing in either vehicle.