Yesterday my DX said my SD card was damaged (just out of the blue, nothing new downloaded or anything). After searching I followed instructions to copy all files to my computer, reformat SD card, and copy files back to it. That fixed the SD card problem. But, in the midst of the damaged card problem my hardware keys (menu, back, search, except for home) stopped working and my ringer turns itself down and on vibrate on it's own. Any ideas what the problem may be? Do I need to SBF?