audio problem (involving quicktime?)

Alright; I recently imported some old videos that were imported on a windows machine to my G5 for use in FCP 6.0.4. Unfortunately, they have no audio under FCP or Quicktime Player.... However, there is audio when played with VLC. The codec (as described by Get Info) is MPEG2 Muxed @ 640x480

Anyways, does anybody have any advice for what I should do before I muck about too much? Transcode to another format, I imagine?

Thanks a ton! I thought that would be the case. And I just went through with your advice and got MPEG Streamclip, converted to DV, everything is dandy.