The first piece is his solo performance piece. The music you hear at the start is him playing an R&B track from his cellphone, into a microphone. Then you can hear him playing the drum kit over the top.
The second is his composition piece. He can't claim any marks for the backing track, which was done by other member of staff, who is actually a pretty decent London dubstep producer. I believe he just found a rap track he liked, and told the guy, "make it sound like, sick, like dis one, like, innit!" or something to that effect. However he DID compose and perform the rap, which is, truly amazing. Enjoy.