Anyone experience this, which happened to me twice today: for the first 10 minutes or so of a one hour drive Nav was updating my location on the map and give accurate directions verbally and on-screen. Then the map froze/stopped updating, but on-screen and verbal directions continued accurately. A few times the map would update to the current location, and then then freeze again for another 15-20 minutes. First time I experienced it Droid X was plugged into the car charger, but second time it wasn't. Anyone else see anything similar?