Further to RB’s problem, I have also just changed to an iPhone and had Bluetooth problems. I run a 2004 BMW 330 convertible with integrated Bluetooth hands free as part of the factory fit satnav. Previous phones have paired with no problems. When I paired my car and iPhone, whilst the phone and car connected they would disconnect after just a few seconds rendering it useless. I spoke to my BMW dealer who stated it is a problem with the data speed / quantity and the iPhone was not considered compatible. There was a hardware solution to upgrade the Bluetooth but it would cost £500. I changed my iPhone settings to just transfer favourites and placed those numbers I am likely to call into my favourites (20 or so). Since then my iPhone has paired flawlessly with the car. This may also work for other cars and Bluetooth devices.