This seems to be a very controversial topic that people usually juggle back and forth between reading and writing. I can say from experience that I have been reading and writing with music for ages now, sometimes music seems to be a calming agent for either topic or it helps play with what I'm writing or scenes that I'm reading.
When I read I find that music helps block out most background noises like talking or screaming or the television, or dogs barking. Now when I listen to music I don't go to songs that stream lyrics that I can contemplate or listen along to and focus more towards than the words of the novel. When I go to Youtube or my iPod or iTunes I find the first instrumental song that I can find. Most instrumental music I have consist of movie soundtracks, video game soundtracks, or even anime soundtracks. When I listen to them it helps build upon the image the author writes and describes. It's more so a pick me up when I can't really get into the story or feel for the emotions. Even with writing, for the writers out there I definitely suggest listening to instrumental music whether it be classical, video game style, movies, dubstep, the list is endless.