Err, no.

The long story - my car has a built-in Bluetooth that integrates neatly with the audio unit that came with it. The pairing is with the car, not the audio unit. It still pairs even with the audio unit removed but, of course, there is no sound.

I replaced the audio unit for one with more functionality, including satnav and its own Bluetooth, thus forcing me to unpair the phone from the car and pair it with the new unit. It is this unit that suffered the phonebook sync problem.

The replacement unit recently gave up the ghost and I was forced to put the original one back in and pair the phone with the car again. Since then, no more missing phonebook entries.

So, I did not fix the problem because, in the end, I did not have to