Misophonia?"Misophonia, literally “hatred of sound”, is a form of decreased sound tolerance, also known as Selective Sound Sensitivity Syndrome or 4S.... misophonia is specific for certain sounds." Also, "People who have misophonia are most commonly annoyed, or even enraged, by the sound of other people eating, breathing, coughing, or other ordinary sounds." (from Wikipedia)
I was told by a counselor, when I was around 14, that I sounded like I had misophonia, although she might have been joking. It's not something that is really diagnosed. But the minute I said, "the sound of others chewing doesn't just annoy me, it makes me feel angry. I want to yell at them - why can't you learn to chew quietly, politely!?"
When I was 6, I would cry at the dinner table because my brother chewed with his mouth open. When my sister would scrape her fork across her plate (sometimes on purpose), I would scream and cover my ears. Certain sounds, like cash registers opening and chalk on the board at school, would drive me insane. As I got older, I learned to deal with it and now I am pretty good at tuning out sounds. Sometimes, however, I will be startled at work by my cash drawer opening. The only sound I can't tune out though is chewing. It drives me insane.
Gum is a horrible invention. I feel like Willy Wonka - gum is gross and annoying. The sounds that come from people's mouths and jaws is revolting and yet, totally excepted. Why is it polite to chew what is essentially human cud in public? Sick.