You've just reminded me - before my leaky-gut diet made it unnecessary, I found that a recording of the sound of breaking waves helped me sleep. I've had trouble sleeping all my life (I am 60) but since changing my diet it is so much better. I can sometimes be one of those annoying, smug people who can fall asleep in 5 minutes! Ten minutes is not at all unusual for me now, but it used to be at least half an hour and often much longer, and the quality was crap too. Now this is rare.