View this video at https://macmost.com/how-to-fade-out-music-and-sound-in-imovie.html. Instead of having music continue past the end of your video clips, or having it end abruptly, you can easily fade out music and other audio at the end of your movie. You can also adjust the volume of audio clips making them fade in, out, cross-fade, do L-cuts and J-cuts, and also manually control the volume at any point you like.