I had this problem once or twice last winter, and I thought it was possibly due to the winter time. However searching this forum, I found some CX7 guys were having the same issues. Turns out it was when they used a power inverter....today I used a inverter. Thought it was intresting anyone else having this problem. Here is the report from one of the cx7 guys
http://www.msprotege.com/forum/showpost.php?p=3434284&postcount=41
http://www.msprotege.com/forum/showpost.php?p=3434284&postcount=41