I'm thinking you're going to have to suffer. What is the point of the bluetooth on the GPS, voiced directions? Stick with the output from the GPS itself no loss. If you're talking on the phone to someone and trying to use your GPS at the same time you probably need to get your priorities straight =) When I'm in heavy traffic not only do I turn my radio off or to it's lowest setting I also tell me wife to shh. I'm all for multitasking, but if you're in a car the only objective you should have is getting from point A to point B without killing anyone => Just because it's voice doesn't mean it's not a distraction, in my opinion the ONLY thing a drive should ever do besides drive is minimizing the distractions that take away from driving. Mind you my commute is 20 miles one way and I also drive our works truck for pickups and deliveries. It's not to say that people can't do things like that year after year without repurcussion, but I have never been in even a fender bender while driving. I'd like to think it has something to do with that mindset, and it should be a more prevalent one.
Sorry for preaching =)