I am now on my third Nuvi 665 all displaying same problem. After short period of working correctly unit stops reporting turn instruction via voice application. Last unit work correctly for exactly three turn instructions before erroring out. Powering down including removing battery sometimes will reactivate voice instruction from unit but only for a few turns instructions. This seems to cause unit to lock up and only removing battery is only remedy to getting any normaly functionality. 1st unit returned to store, 2nd unit returned to Garmin, 3rd unit still in hand but not functioning correctly.
For $800 one would think it should work as promoted.
Any Ideals? Any Help?