All button not function , and select button faulty.

When i turn on my psp, sometimes all button is function but sometimes not. When it's all work never ever press the select button it will be stuck on recovery menu. when iplay any games, everything is ok but when i press home the selection is not blinking and still can back to the game. After exit the game it's stuck on the home screen. All button not function but the background wall paper is still running........