anchor: love.system.hasBackgroundMusic
  Gets whether another application on the system is playing music in the background.
  
  Currently this is implemented on iOS and Android, and will always return false on other operating systems. The t.audio.mixwithsystem flag in love.conf can be used to configure whether background audio / music from other apps should play while LÖVE is open.
  backgroundmusic = love.system.hasBackgroundMusic()
  backgroundmusic boolean True if the user is playing music in the background via another app, false otherwise.