I think its called misophonia or misofonia. Not sure of the spelling. It was on 20/20 on this past friday night. It is where certain sounds make a person literally crazy. They can even go into rages. And it can start at different ages and it can be only certain people...like mom's voice will irritate more than dad's. Things like gum smacking or lip chewing or even breathing heavy can bring people to raging.