I have had this bug ever since 1.13. And I have reinstalled Minecraft and reset my audio drivers and still, nothing has fixed this. Every time I get the Mojang loading screen whether it be for changing settings or changing a resource pack or shader pack the game will lose all sound. Not only that is I also won't have any subtitles for the sounds in the game anymore. The game no longer figures up the sound and it is really annoying having to restart the game just to change a resource pack or settings in the game. Please look into why this is happening nothing I have done so far has fixed this problem.