The control set locked 'power' and 'channels' buttoms, all others are working. I thought it could be low level batteries, and replaced them. Didn't work. Turned off/on the TV, didn't work (as expected). It was working perfectly minutes before, I put the control aside, maybe the pillow touched any keys, so the set just stopped working for those keys - power and channels. I don't know what to do to unlock these keys.