RV770 Voice Command problem


When doing a Voice Command to Find Place yesterday, we found the 770 chokes just at the end of asking what to search for. It shuts down (and restarts, if plugged in). Still doing this today.
On the way in from startup a screen pops up that I've never seen before, announcing that a Map Update was done. Over the air? I haven't done an Express update for a couple of months.
Other voice searches still work fine. The Place search had been working fine until this started. I've fired up Garmin Express to check for updates, it just says the 770 is up to date.
Otherwise the unit is working fine.