I remember hearing a while ago that a borborygmus was the sound of your stomach growling, or gurgling as the case may be. I looked the word up, and it seems that it’s not your stomach growling, but the sound of gas as it travels through the intestine, especially your large intestine.
As much as I’d like to indulge my inner 12-year-old (huhuh… farts… huhuh), I’m going to avoid that particular topic, and instead share an example of the kind of noise I listen to at night to help me get to sleep. In this case, a peaceful forest river gurgling along while birds chirp in the background. It’s three hours long, so I don’t expect you to listen to all of it right now, but it does help when you’re trying to get to sleep.