I've had my Pandigital E-Reader Tablet for about two weeks. I've went out and gotten an SD card for it. I put the SD card into my tablet and now it will turn itself off when I'm in the middle of doing something. I turn it back on and it lasts for about 2 seconds. I can unlock it most of the time, but sometimes it turns itself back off even before then. Could my SD card be too big? It's really bugging me, and I don't know what to do!