I need a bit of ambient sound to block out the auditive hypnagogic hallucinations I otherwise get at sleep time.
I've been using a radio set at low volume for that up to this point, but I've been waking up at night quite frequently as of late.
To figure out why, I've been recording at night. It's been very enlightening. I seem to wake up when I snore loudly and when there's a news bulletin on the radio.
I have replaced the radio with ambient sound from a speaker. I'm still awake now though.