"He turned up at the studio with a guitar on his back, when he was living on sofas", says Jake Gosling, who produced almost all of Sheeran's debut album and parts of the upcoming follow-up. "We found we had the same influences - Bob Dylan and Johnny Cash and Joni Mitchell and all that kind of stuff. Then he suddenly said, 'I love rapping.' But it wasn't rap-rap, it was singing rap...