I've noticed recently that when I enter certain parts of town, the white map turns black. It still shows the names of the streets and only a portion of the map has a black background. When I leave that area, it's white again. It's really odd that you can see the black area as you are approaching, and there are many times when the screen shows both black and white areas. I know this sounds but it's new and I don't like it. I will try to take a picture next time it happens. Any ideas or similar experiences?