This class keeps track of the music it's playing, and adjusts the volume when necessary. These objects are handled by the musicPlayback library.
shufflePlaylist (true)
whether the playlist should be shuffled. fadeInTime (0.25)
fadeOutTime (0.3333)
the divider for the time it takes to fade a track out in the playlist.
maxTracksInMemory (2)
the maximum amount of music tracks we can keep in memory before removing the last one in the list.