The sf::Music object called "music" never has loadFromFile called on it, so I wouldn't be surprised if you aren't hearing that one.
The one called "lalala" has play() called on it in the render() method every frame, which is very strange and definitely unnecessary, though it doesn't seem like that should cause any problems.
Also, it has been waaaaay too long since I studied Spanish. Seeing "ventana" refer to a GUI window instead of a physical window on the side of a house just looks weird to me.