I looked into this extensivley and found out that there is no music provided. A few of the TV's have speaker jacks so you can plug in your CD player but no guarantees. I bought external speakers for my CD player (cost about $25 cdn) and they sound great and are light and easy to pack. I am also bringing my laptop which also plays a ton of music.
I don't understand why the cruise industry, who pays such attention to detail doesn't have some source of music in their cabins. Even on flights there is a selection of music to listen to.
I say if you're into it...bring it.
have a great time
Tom
