No problem here with the iPhone4 and 2011 X5. The most I've had to do maybe once or twice is disable BT on the phone and re-enable to get the pairing established.

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Warning, I'm prone to sudden attacks of enthusiasm





In the garage
2008 Infiniti G37S Coupe (Traded)
2011 BMW X5 xDrive35i
2011 BMW X5 xDrive50i