I have a line scape M.D. 20 stage Scape mixer ; usually when I turn it on it comes up with the stage set up last saved. Now when I turn it on the SAVED seen pops up and then Monitor B pops up. And nothing is plugged into Monitor B and if I plug a cord into monitor B input The icon in the input bar turns off, as if the sensor is switched to the opposite. Is there anyway to return to factory settings to reset that???