I think one of the neighbors is watching porn and it's REALLY LOUD. That's the only thing that could explain the moaning with bad music in the background.
Since when is the allure of pornography the way it sounds?
And while I'm venting, someone needs to tell the kids in this building that the hallways and staircases are not a playground. And being indoors means using your indoor voices. (Writing that last sentence made me feel way older than I actually am.)