It all happened while I was playing Super Mario World on SNES9xTYL when I noticed that Mario started ducking and coming back up all of a sudden. I figured this as strange, so I just quit the game. Now, I noticed that whenever I go to a menu that has more than one icon vertically, and if it does, it keeps going down automatically without stop. How can I fix this, or do any of you have had this problem and fixed it and how?
EDIT: Oh, I forgot to mention that my down PSP button isn't physically "stuck", it still presses down smoothly like the day I've bought the PSP, so it must be a system or a damaged circuit, I can't tell.