For people with the soundtrack module installed: install the mod as normal, except for the Assets/XML/Audio/Audio2DScripts.xml and AudioDefines.xml files. Instead, you download the files linked below, open them, and manually copy-paste what's inside them into those files in your Assets/XML/Audio folder. This only works if you install the soundtrack module first, and then this modmod.
Do not overwrite Audio2DScripts and AudioDefines with the files below. Open them and copy-paste the stuff in the files below into them.
https://www.dropbox.com/s/9lk9cw79k8m8scw/AddthistoAudio2DScripts.xml
https://www.dropbox.com/s/8v0c4drukgfxxlr/AddthistoAudioDefines.xml
Do not overwrite Audio2DScripts and AudioDefines with the files below. Open them and copy-paste the stuff in the files below into them.
https://www.dropbox.com/s/9lk9cw79k8m8scw/AddthistoAudio2DScripts.xml
https://www.dropbox.com/s/8v0c4drukgfxxlr/AddthistoAudioDefines.xml