For me, it's definitively music-free when sailing. My favorite moment when sailing is actually a sound as well: It's that moment after you've set your sails, when you turn off the motor and yet somehow, magically, the boat is still moving forward. It's that moment when I realize that this forward motion isn't burning a limited tank of gas, and yes, I really could go anywhere I wanted.
For rainy, cold winter days, when sailnet and a bookshelf of nautical books are the only things keeping me sane I like Awolnation's Sail
to get the sailing/racing blood pumping.
I also STRONGLY agree that at anchor, especially during that magic sunset time, music should not be heard beyond your own boat. Unfortunately this also seems to be the time that everybody wants to run a genset.