I had intermittent problems with reception. Moved the antenna, re-loaded software, ETC... (very frustrating)
In the end I pulled the unit and changed the position of antenna attachment that screws on the back of the Dynavin. Can't remember the direction I moved it to but it did the trick. No problems since (2 weeks ago). I mentioned this to Jeff B. and he confirmed that this could be causing the problem.
The fit of the Dynavin is really tight. I could see scratches left where the gps antenna connection was hitting (pinching ???).