David Ovalle—also known by his DJ handle, D-Rock—has been spinning records for most of his life. He’s played at baseball games, clubs, house parties, and South by Southwest. He even owned his own radio station at one point. On the night before my visit to his Laredo restaurant, Livi’s Mexicue, Ovalle played a gig at a nightclub that was broadcasting a Canelo boxing match. But the 35-year-old, with a trim, light brown beard and a rigid part near the top of his closely cut hair, has recently spent more time remixing other things: barbecue and tacos.DJing came more naturally to Ovalle at first. “It just called to me,” he says. “I love seeing the way that one person can control a whole audience, their emotions.”…