i KNOW i have it...well, i think it's actually a strange combo of misophonia and hyperacusis. in fact, on the aspie quiz, i scored NT or close to NT in most categories except Perception -- SEVERELY aspie.
i'm startled by sudden sounds, both loud and soft, and irritated by most others. but i can't handle complete silence, either...which is why i use a white noise machine at night -- and during the day! (when on my computer, which is in my bedroom). it drowns out a lot of the little noises and dulls the louder ones.
as for when i'm in the rest of the house, i use the tv as my white noise maker...but i can't handle the volume being too high...nor low, lol.
as for things like someone drumming their fingers, chewing or breathing loudly, or *dragging their teeth across their fork* (OMG, that one makes me homicidal!), i immediately DEMAND that they stop -- if they're family, that is, lol (and it doesn't matter how distant of family, either!). but when in public, i'll simply give the perpetrator a dirty look; and if that doesn't work, i'll move away from the area or leave.
on the other hand, i love loud music -- IF it's music i *like*, that is (but if it's country, i get out my shotgun) 