'07 Nav voice guidance trouble

I recently installed a factory '07 nav.  When I start the guidance the system states "Proceed to the highlighted route and guidance will begin".  No more is said until I reach the destination, "Destination".  I have never used a GM nav, but doesn't it tell you were to turn?  I drove Lexus and Acura with nav and they did.  Any suggestions?

You don't have VSS (Vehicle Speed Sensor) working or not hooked up......     do a search on NAV & VSS & you'll find plenty of info on the subject.

http://www.chevroletforum.com/m_5604/tm.htm
 
Check this thread and it should answer all of your question..