Over vacation a few times, my family would go and stay at a small cabin on a lake. There was always that sort of wave crashing noise in the background. Maybe it was just because the little cabins were built in the 40s/50s, but it would always sound pretty scary when it was stomry out, with the lake getting a bit violent and crashing loudly while wind and rain assaulted the building from all sides.>had a little water trickling fountain in my room for a while, but cat broke it.
Probably not what you're talking about, but I have one for my cat. It's kind of annoying because there's a lot of pump noise at times.