Our cat is also extremely sensitive to sound. I have one glass bowl that I use when I give her boiled chicken as a treat. Somehow she can hear a difference between that bowl and the bowls we use everyday. When I take that bowl out of the cabinet she comes running. It's amazing.
She can also tell the difference between our cars and our neighbors cars (we're in a row of townhouses, so all cars are out front). When she hears our cars she goes to the front door.
Our cat hates the sound of crying babies on tv and she will look all nervous until they stop.