NEW FIRE ALBUM (by Nickname)

Loud sound warning!

Nickname is the name of the lovely gal singing on stage. If you create a song that has h° on every other line, and have said song be sung by a character who's voice is pitched all the way up, shenanigans will ensue. Proceed with caution tho, as this can cause your game to crash, or visual glitches with Mii appearances. I recommend saving BEFORE trying.

Apparently it happens because the way they try to pronounce h° takes 4 whole seconds or something, tho I only heard this from my friend, I have no actual source.