I’m so glad you posted this theory. I’ve come to the same conclusions: my biggest sound triggers are things I associate with someone being inconsiderate of how their actions affect others. That’s why I’m not bothered by the click of my humidifier, but I nearly fly off the handle when someone clicks a pen. I don’t mind the sound of my cat eating, but my coworkers’ crunching sounds drive me nuts. I’m glad I’m not the only one with this theory!