When i checked properties on your wmv video, it reports back as Windows Media Audio 9 - so I don't know what the problem could be. I have had issues with not having tha AC3 audio codec (google for it - it is a free d/l) lately so I downloaded it and all of my audio issues have disappeared.
I encoded it with TMPGenc Plus 2.5
When I loaded the video, the audio popped right in for me.
your download link:
http://www.spiketechnical.com/convert/0721_01_sm.mpg
74mb I know the filesize is large, but at least it is in mpg format and you can degrade it as you need.
good luck with your big project
I'm heading out for the night
ICQ 123050302