Just wanted to share my own experience. For the past couple of years I came across complaints
where owners complaint on strange, unexplainable problems with their cameras, and I suspect it was corruption in settings. I suggested to remove battery from malfunctioning camera and let it sit for a week, in order to drain internal back-up battery and thus loose all and every settings, it will force the camera read all settings from a ROM memory and load in to a RAM memory (or an another type memory, the camera might use). I'm not sure if anyone followed my advicse with success, but when my D7000 started acting - I could not reformat memory card using combination of metering and Delete buttons, also I could not reset camera to factory defaults using Quality and exposure compensation buttons. All buttons are working correctly individually, but the shortcuts when pressing and holding two buttons together did not work. It warmed properly if I go into the menu - I can do all functions from there. But resetting to a factory defaults using the menu, it did not fix my problems with shortcuts. Who knows what we was malfunctioning or would malfunction. So my game plan was first to remove the battery and drained the internal backup battery until all possible settings are lost. If it would not fix my problem I would try to re-flash the firmware.
So I started by removing battery from my camera and let it stay powerless for about a week - that was enough time to drain out the internal battery.
After first startup after that, my camera booted up to a factory defaults. And my D7000 functions correctly now. So I don't need to reflash the FW. Simple but very effective DIY fix
Hope it might help some people to save on out of warranty repair.