RCA lya 1072B

Question

Was working fine ~6months. Then out of no where I noticed all the keys not functioning. It does turn on, but won't skip, change modes or anything. (won't shutoff even)It's not locked. I've tried reloading different songs. I've tried reformatting the drives. (internal & flashcard)I've tried without the flash card. I've tried different batteries. I've tried leaving it alone with no-battery...Any ideas ?