T-Axxi

Hi Guys, my father recently purchased a 04 Lexus LS430, Beautiful car, we love it, only real issue we have is with a handsfree kit from Parrot, we're having trouble installing it. The Brain-Box doesn't switch the radio off when a call comes in or play personal audio, which it's meant to do. Anybody ever had any issues with Parrot systems in this car&model, any solution to a good handsfree system? Even if it isn't a Parrot system, all solutions are welcomed