Cant recognize mp3

Hi.I have sansa sandisc 2gb.I havent use it for some time and now my computer dont recognize it at all (when i plug it sometimes down right comp says "found new hardware " ). Mp3 is on and on display is “conected”.Battery is sometimes charging for a minit or two and then stops (then after few mins i again hear “boop” and battery is again chargin for min or two )

Switch it to MSC mode.