LOS ANGELES — R&B singer Chris Brown has tested positive for marijuana, leading a Los Angeles judge on Monday to set a November hearing to decide whether he violated his probation stemming from a 2009 assault on then-girlfriend Rihanna. According to a probation report presented in court, Brown tested positive in June in Virginia, where he is fulfilling his community service, Los Angeles Superior Court Judge Patricia Schnegg said. Brown, who is midway through a five-year probation sentence, produced a medical marijuana card after the positive test, Schnegg said. Schnegg said mandatory drug testing was not a condition of Brown's probation. But she scheduled a Nov. 1 hearing to decide whether he had violated his probation on that and other matters, including travel restrictions and fulfillment of his community service. Schnegg gave Brown, 23, a warning in court, reminding him that he was a role model. — Reuters