Music and Mind
I agree people hear different things in music, and not even just musicians vs. non-musicians. If you take an album like Laughing Stock by Talk Talk, as a musician, I still hear something new each time I listen to it (that has more to do with the endless layers than anything, I guess). Another interesting thing I've noticed is that I sort of log songs I hear casually into "like" or "dislike" categories, but subliminally. I'll hear a song in a store or something and either immediately be like "ah what is that, I like that song", or the opposite. When I realize what it is, I might be sort of embarrassed at myself, if it's, for instance, a Katy Perry song I was enjoying. This is apparently based on the social acceptability of certain music within certain circles, which goes into another topic, but the point is that apparently I don't even always hear the same song the same way; i.e., I may not realize I instinctively
like a song or piece until I hear it in a new context.