Add an option to fix unnatural chopping of some notes (change the number of voices?)

[loveemu]

Some notes get unnaturally choppy. However, this is not rip's fault; it is as it is in the game.

https://youtu.be/3TKCnHlpMfw?t=640

• Commit hash: 7c7439a7 (download)
• Game: Harry Potter and the Goblet of Fire (USA) (sha1: 951f311d9a99920abdbb9134ac8b9d00dfdb9b0b) (GAX 3.05A)
• Song: CC_GBA_COMC_Wander_03
• Player: GSF Decoder (foo_input_gsf) 3.0.21 and mGBA 0.9.1

It would be great if there was an option to fix this.