The radar hum that never goes quiet

I'm sitting in a dark room with no windows and the radar blips are drifting across the screen in no kind of pattern, and all I'm doing is listening to the hum it makes. There are no calls, no squawks, just that constant clean tone, and it's pressing down on me from every direction — heavier and heavier, heavier than the air in the tower ever was. I wake up and my ears are still ringing with it, and for a half second I'm honestly relieved it's over. But I'm not sure it is.