I've got an old release of option 11 that has wallboard problems. The wallboards are connected via rs232 to a controller called a MCK SWD Controller, this then connects to a digital station port on the option 11 which has the queue info programmed on it's buttons. I've proved that the contoller is faulty but can't source a replacement by that particular manufacturer. Does anyone know of a similar part that does the same job or where I can get a replacement part for what is currently on site.