All of the game's music in MP3 form. Sadly I don't know the names of the tracks. Motoi Sakuraba, who composed music for the previous two games, returned for Annet Futatabi.
-The intro theme, which is the only tune with lyrics, is also the only one not to be done on the Redbook format, hence why the quality of it isn't as good as the other tracks.
If you want the lyrics for the intro, click here. Thanks to popfan95b for this.
-The music track for the second level is rather long for what it is, as the level itself is really short -after defeating just two enemies, the boss music will then start to play as the boss appears.
-Levels 6 and 8 are boss only fights, so they use the boss music throughout.
-Level 9 is a boss only fight, but it uses the same music as the first level.
-The unused track can be heard in the music test in the config menu, it's no 7. Maybe it was an alternate, unused theme for the game's credits? I don't know where else it could fit it.