I must have noise to go along with going to sleep. Usually thats an audio book or long-form video essay type YouTube videos. I wear one earbud to bed if I’m sleeping at night with my girlfriend or just blare it from the TV if I’m sleeping alone during the day (rotating shift). I feel like when I don’t have engaging audio and I’m trying to sleep I can’t quiet my mind enough to sleep. A fan or random ambient noise isn’t enough for me.
No, I cant sleep with anything with vocals in it. My brain strains too hard trying to interpret or ignore it. Non-vocal music can work very well at low volume as long as its repetitive and thus predictable enough that my brain doesn’t have to pay attention or react to a lot of changes in composition.