This game only plays voices if it can use the Steam API to geolocate your IP to an Asian country (didn't look at the full list). Since this post uses a Steam API emulator that doesn't support changing the result of geolocation, I fixed the game to play voices everywhere.
Download https://pixeldrain.com/u/cg6TZxiS, decompress the .7z, and replace the game's GameAssembly.dll with the one you downloaded.