Oak, Skylight, and Lincoln “separate” and “combine” switches do function as intended. It is possible to play a CD or other audio source through the Lincoln room speakers and not the Skylight room or Oak room. It is possible to have a microphone being used in the Oak room without sending the audio to the speakers in the Skylight room or Lincoln room. It is also possible to combine the Oak room and Skylight room audio while keeping the Lincoln room audio separate. It is also possible to combine the Skylight room and Lincoln room audio while keeping the Oak room separate.
The Lincoln room and the Skylight room has solid wood doors between them creating a better sound barrier. The Oak room and Skylight room have doors with full length glass panes, making a terrible sound barrier. Audio from the Oak room can be heard in the Skylight room due to the glass pane doors. Audio from the Lincoln room is not as audible in the Skylight room but can be heard slightly.