I have written a perl interface to the MAD mpeg decoding library. I have written several pure perl mpeg players using this library, it's Audio::Mad and it's fairly alpha just yet. It hasn't received much testing and I haven't advocated it's use too much; but it works for me. I also wrote a POE component based on this module which handles the decoding process on it's own and sends out status updates. It's not released, but if you're interested, I could easily put it up.