I was working as a parking attendant at a big music festival in the early aughts and got a bad sunburn. When I got home that evening I turned on the shower and was getting ready to get in and I swear the rhythm of the water falling sounded just like mariachi music. I'll very occasionally have a similar experience when very tired or otherwise under profound physical strain but that one time with the mariachi music was the most vivid by far, and it continued for the entire shower.

Edit: I'm glad this sort of thing has only ever happened to me rarely, and in safe, familiar environments. I would get pretty spooked knowing I was having strong pareidolia in an unfamiliar place, no matter how beautiful the scenery.