How does the music and soothing sounds feature work?

The music button selects music and all ten songs will play in turn before starting again with the first song; you can skip a song by pressing the button. The soothing sounds button selects from five soothing sounds from nature (womb sounds, stream, forest, white noise, and distant storm) that will play continuously until a different sound is selected. Music will automatically shut off 60 minutes after the last button press or speed change. (Page 19)