Recently, my Tomtom Rider 550 becomes stuck when placed on the docking mount. This happens every time it is mounted. It's nearly impossible to remove the unit from the mount when this happens. I've had to resort to sliding a thin piece of plastic between the GPs unit and the mount to separate them. I don't see any obstructions or reasons why this is happening now. It had worked flawlessly from 3 years until I installed it last week.