I have a Nikon D510.0 When I bought the camera at a independent camera shop, I also bought on their recommendation 2 X hama SDHC 4 GB cards.However from time to time when I switch the camera on or in the middle of a shoot the screen on the camera tells me that there is no card in the camera. I then have to switch off the camera Pop out, then Pop in the card and it works fine till next time. Has anyone experienced the same problem?