Pacific Power customers in Roseburg, Winchester, Sutherlin and Oakland briefly lost power this morning after a transmission line to substations in those areas went out. The outage affected 12,253 customers and lasted about 25 minutes, Pacific Power spokesman Monte Mendenhall said. The power went out around 8:50 a.m. and was restored to all customers by 9:15 a.m., he said. Pacific Power was investigating what caused the high-voltage transmission line to fail, Mendenhall said. …