I have a strange problem today. Until now, my NEX-7 worked perfectly fine. But now, when I turn it on, I can't do anything. It shows the scene as usual, but none of the buttons do anything - it doesn't even show the buttons on-screen at the right like it usually does. However, I can manually focus E-mount lenses as always. After trying different setups with many lenses, batteries and SD cards, I know what causes the problem - the SD cards. When I turn it on without an SD card in it, everything is fine. But as soon as I put an SD card in, it doesn't work. But obviously, I need to put an SD card in. So what could cause this? Any ideas? Edit: When I turn it off and back on with an SD card in it it does one of the two things: Just turning the screen off and back on or turning the camera off, but when turning it on again it just shows a black screen.