2016 R1200RT, Bike is relatively new to me (less than 1,000 miles) and came without navigation. Bought a used Nav v off of ebay. I am familiar with Zumo 390 and they seem much the same. Seems to work fine except for no navigation voice prompts. The wonder wheel will work to zoom in and out but will not work to toggle the "speak" or "mute" menu choices. Ideally I would like to get the voice prompts through the bike speakers without having the radio on. At this time I get no prompts with or without the radio on. I have made sure the unit is not muted, I have cleaned the contacts with alcohol, I have done a reset to factory defaults, finally I did a hard reset by disconnecting the battery and reconnecting it. HELP