I’m not an amateur videographer…I don’t use camcorders in other words. I do a far amount of avi to dvd conversions and I use ProCoder, but I don’t use the Wizard.
The file you have from WMM is a dv-avi file yes? Can you open it with Virtualdub? If so, you might be able to extract the audio as a .wav file. http://www.videohelp.com/oldguides/virtualdubaudio
Then convert the avi file in ProCoder and do not have it output any audio…you’ll have to adjust that in the Target settings. I suggest using Mpeg Mastering Quality, then go down to the Audio section and change audio from Use Always to Don’t Use.
The resulting file from ProCoder will be a .m2v file…mpeg2 with no audio. At this point you might want to convert the .wav audio file to ac3. You can do this with ffmeggui or Besweet + BeLight.
Mux (combine) the two together with TMPGenc using the Mpeg Tools section. Test this resulting mpeg2 file for sound quality and audio/video sync. If you run into a purely synchronization problem, adjust with VideoReDo.
Since you already have the mpeg2 file with the bad sound, you might not have to reencode the whole thing. You might just be able to demux the bad sounding mpeg2 file you have now with TMPGenc Mpeg tools, giving you a .m2v file from it, then go through the process of removing the audio from the original avi file, remux and produce your “good” mpeg2 file.
Lot of trouble, but might work. If all goes well, you’ll have an mpeg2 file that I hope you have encoded to dvd specifications :). Import this to an authoring program and produce your finished dvd. There are several free authoring programs, like DVDAuthorGui or DVDStyler, but you may already have one.