It is related to a random meditation video I ripped to MP3 which generally works well.
"Fall Asleep In MINUTES! Sleep Talk-Down Guided Meditation Hypnosis for Sleeping"
Don't let it play past the first hour though. A glitch will wake you up again.
I use JetAudio's timer to start brown noise after 30 minutes, with the meditation played in another audio player.
If you can hum and whistle at the same time you might have a chance.