Actually, I just got an 08 Focus, and a new Zune, and I'm getting the exact same issue. Only a few min. down the road it will just cut out. Little upset myself considering I just got a job with Ford, and was pretty excited to find out what Sync was all about, only to have a problem right off the bat. I haven't even had the car for a week. Where are you guys posting the problems, so they know the Zune has them too? I'm having a problem with my phone as well, anyone know why sync may not recognize multiple numbers for the same contact? It will only call on "other" even tough there are cell, home, and or work numbers stored for someone in my phone book.
So far this is the only place I've found even talking about sync problems...