It is asked a bunch. Do you listen to the same music when you are writing or do you vary it? Do you listen to the type of music that will be reflective of the writing you are planning on doing, or is it the opposite and the music you listen to changes what you are writing?
I listen to various things and will often key what I am listening to to what I am about to write but that is not always the case. If I just need some noise I will put on music that I do not know the words to so that the music will not distract me and just provide back ground noise. If I know the words to the music (I know the words to most everything I listen to) then I may get more caught up in the music than the writing.
Oops, while typing this Mumford and Sons stopped, now I have put on Outkast.