If the car is new to you then it is best to reset the satnav. you need to enter the satnav diagnostic menu and clear satnav ecu ram. This will reset the satnav to factory defaults but not change the version. You will lose all route info that you may have stored.
One of the set options for the option button is to turn off audio navigation. I do this on journeys where I want traffic information etc but not the women's whiney voice. Traffic Info still comes out at the preset volume.
IncidentallyI don't like the way the audio turn by turn instructions are longer and more 'flowery' on the 9G. We now get 'in about' 100 yards' rather than the 8G's 'in 100 yards'. We then get 'turn now, TURN NOW, at junctions but often a little to soon.
In the brochure (holland January 2012 version) it says it's possible to see turn by turn on the I-mid console. But, in de newer brochure (July 2012) it's not mentioned anymore, just like the follow me/coming home lights.
There's not a lot you can do about it.
I think I make a brochure with specs like a Ferrari and sell a VW, just change the specs afterwards.