After languishing in storage for about a year, I recently retrieved my DS Lite so I could play Giana Sisters. I immediately noticed that the bottom screen flickered whenever I pressed any of the main buttons (y, x, b, a). I wasn't sure what to make of it, but I ignored the problem and continued playing. Soon thereafter the DS just shut itself off. I turned it back on, started the game up, and resumed playing. A few minutes later it shut itself off again.

The unit is charged and has no visible physical damage. I am not technically savvy when it comes to the inner workings of handhelds or consoles, so any advice would be greatly appreciated. I'd prefer to try and repair the thing as I'm on a fairly tight budget and have Xmas looming on the horizon. Thanks all.