I have managed to sinc my Nokia Lumia 1020 and factory car charger with my vehicle radio via Bluetooth and it works fine for phone calls. However, turn-by-turn audible directions do not function when Bluetooth sinc is enabled. Voice commands from the maps are totally silent in this mode. That said, turn-by-turn directions DO work when not connected to Bluetooth, but only then. I am guessing that it is a software issue having to do with the navigation application that I am using and that came standard on this phone, but I do not know that for sure. Any help on this topic would be greatly appreciated. Thank you in advance.