I'll be honest with you, I didn't know how to synchronize voice with subtitles. I did it for the Windows build by reading what's being presented on the screen, but for WebGL build, the subtitles lags for some reason (I guess the framerate in browsers are slower so the letters come slower then the audio which is at constant speed). Still have no idea how to fix that...
Also, I experimented with the volume of music and thought I hit the right balance between voice and music, to have that eerie feeling of something happening behind the scene. I guess for some I didn't do well. Thanks for the feedback, will improve next time!