I have never found sound to be a problem until now. I live on a street where, with the exception of cars, the side walks and the street are unobstructed concrete. My second story bedroom window directly faces a dryer vent that sits at street level across the street. The dryer, when on, produces a high pitched noise that is audible when you are outside. The city where I live came out and measured the sound of the (empty) dryer and the sound fell below the threshold of ‘permitted’ noise. However, when you are in my bedroom, the sound is quite audible. This high pitched noise not only penetrates my home but is loud enough to record on my cell phone and wakes me up at night. This noise fills my home. Ear plugs are so so and closing the windows tight does not diminish the sound. I have tried working with the people who own the dryer but they are most uncooperative. It seems they believe I am preposterous and they consider the matter closed. How can I block this noise? The windows in my room are bay windows that take up a good portion of the wall. Surely this problem is not unique to me, and I am interested in hearing on the nature of high pitched sound and how to counteract it so I can have peace and quiet back in my home!