Have had a Garmin GPS for about 3 years now. It has the suction cup device to stick it to the windshield. But lately I have found it keeps falling off randomly. Is the suction cup wearing out or is my windshield just dirty. I can see where I’ve stuck it plenty of times and even using window cleaner and the ring it leaves behind does not go away. I’ve resorted to not even mounting it sometimes because I don’t need a GPS to keep falling off, I don’t want it to break.