I've loved all of your animations on Newgrounds thus far. But as a musician, this one really hits home. I cannot imagine what it would feel like to be deaf. I would probably rather be blind. I know what Beethoven became deaf in his later years, and I wouldn't want to suffer the same fate. Composing would become incresingly more difficult...
As for the animation, I love the scenes you picked to show. Everything was relevant, and bound together nicely. You used this a lot, but one example is when in one scene, the character throws the bottle, and later on, he cleans it up. The angles you used were great!
The music is wonderful as well. It really shows what an impact just one intrument can make (though there was some percussion, but even without it it would've sounded amazingly).
Another thing you did well was the way you chose to play some of the sounds to the audience, but not others.
If I would have to mention something that could be improved, I think it would be that some of the movements felt unnatural (maybe a bit more choppy/jumpy that high budget animations). But I totally get that I can't realistically expect you to tweak every frame to utter perfection, and it removes nothing from the story. The story, which by the way, is simple and effective. You are great at coming up with powerful concepts.
So all in all, brilliant work, and I am eagerly waiting for more of your animations in the future :)