You're not alone. To me is a matter of if I have to _think_ on what I'm doing or not. During graphic design work, music allows my mind to wander and be more creative; I could say I _need_ it. But during coding is more difficult: I can listen at low volume some instrumental music while coding CSS and HTML; but for Javascript or other programming languages I need no music (but not necessarily silence, I can code with mild background noises).