yeah, I know what you mean. Well, unless you're talking on a deeper than physical level- I am distracted often (ok, all the time) by thoughts like this, and by the time I can tear my attention away from whatever new revolution is occuring in my mind, I have no idea what is going on around me, and people always have to repeat things. My friends get really mad sometimes. Also, I will hear really random phrases that make no sense in the context of the conversation, but have the same basic sounds as what they are saying. Something about intonation, I don't know. I think my hearing just really sucks.
There are other times, though, where someone will say something and it feels like there is a meaning to it I am not grasping. Sometimes it's phrasing, but usually it's facial expression or intonation... like all that I get from it is the idea that there is a connection I'm not making, a meaning I'm not grasping, but nothing about what it is. It actually happens a lot, but usually only really mildly.

I'm going to go read it! Yay!

And I hate asking more than once for someone to repeat something. If I don't hear it the second time I usually just nod and go "mmm," and hope it wasn't a question. Or, you know, a declaration of love.