This morning, DCist heard more complaints from District residents about yet another loud racket which woke them up a little earlier than they would have preferred. Fortunately, though, we didn’t have to go on quite the same kind of wild goose chase to figure out what happened this time — Arlington’s alert system filled us in that, indeed, the booming noises were again blank cannon blasts, fired during a drill conducted by the Old Guard’s Presidential Salute Battery.