You can get all the sound through the Bluetooth headset on the phone, I have used this method on a number of HTC based devices:
fire up your reg edit software
go to HKEY_LOCAL_MACHINE/ SOFTWARE/ OEM/ VoiceCommand
Change the Launchapenable from 1 to 0.
Once you have done this exit the reg edit application and press and hold the power button until the devices asks about switching off, tap the yes button to de-power the phone then switch it on again (this is the most reliable method I have found for saving reg edits to the device).
I was using this set-up for a while, the wife doesn't like the sat nav voice - it is also handy if driving at night when the kids are napping - Mike |