I'm not clear on exactly where you're seeing the "info" that you describe, so this may or may not be relevant.
There are currently problems with the way that MP3Tag's encoding of numeric strings are interpreted by Windows - particularly the "length" value (TLEN). This has happened since Windows update KB968816 (Sep 2009), which seems to have instigated stricter enforcement of ID3 standards. More details are here: /t/9209/1" target="_blank">/t/9209/1 .
Regards,
gvm