Oh, that IS interesting... For me, just owning a GT, I don't have UVO GPS/NAV, I've just been using CarPlay anyway. Just talk and tell my phone to go to xyz, customer, etc... So I guess I don't have the issue. Now, when I back up, the sound does go down so as to hear the beeping and warnings. I "think" that is deliberate, but the sound, as soon as shifting to D, goes back to normal levels and position...