Every since updating my Switch to 1.16, I can barely hear any music or sound effects on all volume levels, including maximum volume.  I have uninstalled and reinstalled the application without resolution.  The issue persists on realms as well as local worlds.  The volume is so low, even on maximum volume, that I can't hear footsteps on grass or stone blocks, making mobs nearly impossible to hear from the built-in speakers. 

I was able to plug my switch into an external speaker to hear the game audio and would try my bluetooth headphones if the system was compatible.