When I was in my mid-twenties, I had a boyfriend who had suffered from a series of ear infections as a child (he'd had tubes at one point), and he was VERY sensitive to certain sounds, especially loud cracking/clapping like thunderbolts, firecrackers, gunshot. He would cup a hand over his ear and actually kind of hunch up/cower. I remember feeling bad for him, but not really understanding his suffering.
About a decade after he and I broke up, I suffered a series of middle ear infections, and now have mild high frequency hearing loss in my right ear, as well as a permanent buzz/ring in the same ear. I'm just now getting over a month and a half of Eustachian Tube Dysfunction, too. I never had any trouble with my ears as a child, just an adult, and now that I've suffered through these infections, tinnitus, etc., I've become sound-sensitive. Loud noises, certain voices, music...it all feels like it's actually striking the eardrum of my "bad" ear.
The sound of music -- which used to thrill me -- has become so annoying that I rarely listen to either the radio or the music I own and love. Instead, I listen to talk radio programs on NPR. And the other thing is...I have to listen to talk radio with the volume turned way down...if it's louder than a certain level, my right ear (bad ear) starts having involuntary clicking/fluttering spasms. This particular symptom is called middle ear myoclonus. I take a prescription muscle relaxant "as needed" when my ear goes too crazy. It seems to help...or at least, to calm the flutters for a few weeks.
And I don't have an answer for why any of this has happened to any of us, and neither does any doctor I've met so far.
I just keep the music low or off, and try to avoid stressing over the changes that have happened.