S.S.
I have a twenty one year old who does the same! Just kidding around. Anyway, someone said autism, possible deafness, or too busy. All relevant to two years old. If he is listless and has other signs of terrible behavior take him to the doctor or have him tested as he approaches preschool age (do you have him at home all the time?)
I am partially deaf, but have gone on in life pretty comfortably. And there is a load of help out there for all sorts of these situations. Not to worry.