Open the settings file in notepad. Change music volume from "0.69" to "0,69" (or just 1 to be sure).Dev must've screwed up with the decimal separator somewhere
Ah, looks like I did not account for different decimal separators in different countries.
You can also just delete the settings file and it should re-generate with the correct separators for your location.
I'll try to cut a new release where this isn't needed shortly. Thanks for the help!