iBook Sound Output Problem

I'm on my iBook G4 running Leopard (most recent update), and my sound output, all at once, failed completely. I can plug in headphones, speakers, or just use the built in speakers, but no matter what I use it still says that no output is available. I've restarted, run a disk check, and all that, but the problem has persisted for a couple days now. I really don't want my iBook to be mute forever. Does anyone have any suggestions?