For avi’s use VirtualDub (http://www.virtualdub.org)
1. Open the file in VirtualDub, then click file, save wav. That’ll save the audio part.
2. Now go to audio, select no audio. Then go to video, select direct stream copy. Finally go to file, save as avi, and you’re done saving the video part.
I use Video mp3 Extractor Pro 2.0 (www.geovid.com) cause in difference of other extractors it has a Batch function. So its much more convenient to extract audio from a group of files, then using the other ripper...
This is an old question, I think, there are tons of program can do this now.
Just convert video to music format like MP3, AAC etc with Video Converter.
It’s what you want: extract audio from video file
I use streaming audio recorder free version to save audio from video as MP3, WMA, AAC, OGG and so on directly. You might try this way here: