therockandroll99

So i have the Pro media 2.1 Computer speakers, i found them at a thrift store, the bass worked from the sub woofer for a while, but now i only get a little bass from the satellite speakers, which work fine. Sometimes the sub-woofer will work for a little bit when i plug in the pre-amp input, and then cuts in and out randomly afterwards, and i haven't looked inside to see what is broken, i'm not much of a circuit board guy, but i think i'll be able to figure it out with a little explanation. Could anyone help?