so as some of you may know, sk will be implementing a youtube player in the near future. what i was thinking is that some of us are in crowded areas, and the sound from one persons may leak through to the other, so i was thinking that sk could add some form of headphones, that you link with the player, and wear to hear the sound.
I would assume that the sound would be individualized because it can be so there is no need for extra complexity, especially complexity that cannot be achieved without mods.
The players are strictly client side sound. What OP is proposing requires a server side custom backing more complicated than the players.