I am retrofitting an RNS-E to my A4 B7 which is going OK as I previously retrofitted an RNS-D to an A4 B5 znd got it fully functional, even my local Audi dealer was impressed.
This time I am a little confused by the Navigation/TV tuner. What does it do for navigation as I have no interest in TV in the car.
If it serves nothing useful for the navigation I am tempted to use the connector on the head unit for an aftermarket bluetooth music interface.
The CD changer connects direct to the head unit as does the GPS anttena.