You report it secretly, and they don't know who it is.

But maybe the police came and educated them, and two days later they were still the same. After all, a leopard cannot change his spots.

Maybe they know someone called the police, and the stereo will be louder in the future, thinking, "Call again if you have the ability." You know they have no quality, and even if they did, they wouldn't turn on the stereo at 3 pm.

I see you mentioned the landlord. You all rent houses, right?

I can't take it anymore. I can only consider changing houses, alas ~