Is a depressant. Or perhaps it is far too relaxing to the mind.
What I'm saying is, the music literally puts me to sleep. So I tested this today, I turned the music off and played Valmar's Moon - Milennia's theme from Grandia II in it's place(via Winamp). And what do you know? I was wide awake. Another player I met also has this problem with the music. To my surprize some of my friends have the music turned off as well.