Hi,

Play the AVI using Windows media player, do you hear any sound? If no, it means you are missing a codec and will need to look for the codec to install

If yes, download Gspot and run the AVI thro it. It will give you all the information of the AVI. Usually AVIs will use LAME MP3 or some other common codec but if yours is something else, DVD santa may not be able to recognise it.

What you can do is to use virtual dub , extract the audio file, convert the sound track to LAME MP3 and then merge it back into the picture. Do note that sometimes it will not synchronise properly with the picture.