You will hear that the first few notes have a slight "clich" (that a word?) to them...you have to "pick" the strings, almost as if you are trying to get a pinched harmonic, but don't over do it. It just creates a warmer more alive tone than a duller note played on its own :)

Oh, and don't forget to play at the neck pickup (i.e. your picking the strings AT the neck, not above the treble pickup or middle of them both) :D