My D700 is almost 4 years old and works perfectly as far as I can tell. Last night I removed the lcd cover to clean the screen and noticed spots under the lcd, you can't see them when there's an image to check but you can see them when there is no image. Is this a sign that something is going bad? The spots are concentrated on the left side. I'm thinking about sendindg it in for a CLA after the basketball season because I get cleaner iso 3200 - 6400 images than what I get with the D300s. Anyone experience something similar?