Same here. Pretty common problem since 3.5.1 across a range of models. Some of the folks over at syncmyride have taken it into the their dealers. This is what they are hearing:
"Within 2 days, Ford set me up to take the car to the dealer for evaluation. Corporate personnel, working with local technicians concluded that NO FIX IS CURRENTLY AVAILABLE. I was advised that a team of Ford Engineers has been assigned to correct this malfunction."
"I took my car in for this and the report I got back basically says it is a known issue and engineering is working on it."
"Took it to the dealer and the instruction was ...PROBLEM UNDER INVESTIGATION. DO NOT ATTEMPT REPAIR AT THIS TIME."
"My dealer says that Ford has no solution and no ETA for a solution."
Another "fix this, break that" update from Ford and those of us afflicted are stuck with a broken Nav system until they decide to fix it I guess.
.......here's a lockpick. It might come in handy if you, the master of unlocking, take it with you.