You may have a problem with this application if you use Sound Check setting or gapless album file option in iTunes. It doesn't filter out the MP3 comment frames that iTunes uses for volume normalization data and gapless playback flag. The end result is that if you use Sound Check or gapless album option and don't already have a MP3 comment frame with blank Description field (this is what iTunes displays in Get Info dialog), you can't enter a comment for your file. The application will only load one of the special comment frames created by iTunes, neither of which you would wish to overwrite.