Ok guys, I flew today from Dallas to Tucson and went from CST to MST - a one hour time difference. Maybe I am misunderstanding the sync function. I THOUGHT that once I turn the unit on, I go to the time page and just press sync. From there it would use satellites to determine my location and set correct time. This just didn't happen. Do I have to manually set the time and THEN press sync? If so, what is the purpose?