Country Music duo Brooks & Dunn were forced to cancel three performances last week because Ronnie Dunn had a severe respiratory condition. "I'm sitting here sick, pretty bummed out, with no voice," Dunn said on the band's official Web site. The performance for Sept. 11 in York, Pa., was canceled while the Sept. 12 performance in Pittsburgh has been rescheduled for Oct. 15. The Sept. 13 performance in Chicago has been rescheduled for Oct. 16.