Totally my fault. I asked her if she wants to have the AC set up before her stay. She didn't want me to set it up. But NY weather is unpredictable. It got pretty hot while her stay and she had to sleep with open windows. The windows are sound proof and the AC is up and running. So you won't hear much noise. Remember, the apartment is in the center of New York City in a prime location. It never will be as quiet as somewhere remote in the mountains or similar.