when you sync/update the database you it will stop updating the database once it finds a mp3 file.. with the following:

any ID3 tag that contains more than 255 characters.

The only workaround is (except from retagging the offending MP3 files) is to change the database table to have all the ID3 tag fields present be Memo type fields.. then you run the update... once the update is done you have to change the field type back to text, 255 characters. Frodoplayer doesnt do well with the Memo type fields...