Piano song?

I watched this film on youtube, and later bought the Olive DVD and noticed that there are two different piano songs, when Liv is watching a piano concert after the rape scene, anyone know why there are two different versions? I much prefer the song that plays on the youtube version. I wonder if it's a real song/is available somewhere? Also, since there are two different piano songs, what else is different between these versions? Any help would be appreciated!