"I have no technical ability and I know nothing about music,"
My understanding is, he can't play the piano, guitar or drums at any level of expertise, so I do think the first part is right
now he's a kick-ass turntablist, so that's some technical ability that he's shrugging off
little hyperbole in the second part, but he's not classicly trained and don't think he can even read sheet music
Although, this could all be made up in my mind as I'm a little obsessed with Mr Rubin as of late