volume levelling / gain calculation not working in some files on an album

[bailso]

I recently used DVDAudioExtractor to create some WAV audio files. The software seemed to create tags for some files and not others. Those with tags are ok when calculating volume levelling values but MB is unable to calculate these values for those without track/title tags. In addition when I use the filename to infer tags, that works but if I then (unsuccessfully) try to calculate the regain values again the tags are removed.
I would appreciate any thoughts on how I might overcome this problem.
Thanks

[boroda]

i would convert wav files to flac 1st. wav files have very poor (if any at all) support for tags.