Right, VirtualDub will 'dub' a Wav file on to an AVI file, but I've never found any function to save the audio from a video file. I have a copy of Arcsoft's Showbiz which came bundled with a video capture card from a few years ago. It seems to be able to open a lot of different video file formats and by using right-click popup menu on the video file, it will allow you to save the audio as a Wav file. Just FYI in case you may find a copy somewhere. There seems to be a free trial of Showbiz DVD available on the web, but that's not what I have. I don't know if it has this same popup menu or not.
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