Let me begin by saying that I am addicted to my D800. I am in the North Dakota Oil Patch and my job takes me all ofer. I drive with the camera in my lap, ever ready. The camera takes both CompactFlash and SD cards. Recently the SD card, which engages with a spring-like action, won't engage. Yesterday when I was at home, reviewing the day's photos photos, the "multi selector" button wouldn't work and at the same time the "main command dial" wouldn't let me scroll to the next photo enlarged. Today the latter problem is not in evidence. I was happy to read elsewhere that Nikon is quick with its turn-around, but has anyone else had these problems? Thanks.