Not so much unusual as desperately picky. I take an MP3 to the grocery store to keep from being driven crazy by the music they force upon us there... I think they're aiming at my demographic, but since I don't blend in with said demographic, the music misses me completely. I was ready to smack my head against the floor today at IKEA (Hall and Oates, shudder). I don't like music that I consider boring or common, stupid or lacking whatever qualities I like. A long list of traits will make a song acceptible... smart or funny lyrics, a rhythm I like, some feeling built into the musical that I like feeling, a pleasant association, or just a musical form I like. I tend to take a song and obsess it to death so I try now to hold back a little when a song strikes my fancy.
In short, I have a sort of buffet kind of musical taste... Very few groups appeal to me in large amounts. Only They Might Be Giants seems to get into really high volume on my MP3, with others coming close. I have actually managed to get burned out on the Beatles, as hard as that may be to imagine. Took 25 years, mind you. Took the Beatles themselves less time than that to get burned out...
I like classical when I paint, new age when I write or do ink work, rock and roll when I drive. I have learned to reprogram a song that is stuck in my head, sometimes easily and sometimes through tremendous mental and even physical strain (when the mental strain overflows). I sometimes have an almost obsessive need to sing along, to the point that if the song I want to sing is in another language I will make the effort to learn it phonetically. I often cope with stress by singing.
Music, as I found long ago, has such a strong effect on me that I feel the need to keep from being subjected to anything that would cause me to feel other than I want to feel. People affect me similarly, everything seems to. It sometimes feels like I can't truly be myself unless I am completely alone. I feel like everything around me is trying to reprogram me. Funny for someone who tends to have no empathy or sensitivity generally.