TurboExpress barely audible

I just picked one of these up and when you are playing a game, even with the volume turned all the way up there is almost no sound, it sounds fine with headphones though. Anyone else have this problem, or know a easy solution? I thought the speaker was just blown first, but when I finally got to play it somewhere besides the damned noisy subway, there actually is a faint sound coming from it.

Check your volume control switch, sometimes, they become loose and you have to push them a certain way as you turn the to get it to work.