The music completely turns off after I raise the volume from zero. I occasionally like to listen to music or videos in the background so I temporarily turn off the in-game music. After I'm done with said background music/video I go back into the options to listen to the game's OST but to no avail.

I also tested this out with the main menu music and it seems to be a problem there as well. I have to completely exit the game to get this working again. As of the moment I have to turn the game volume to 1.