The phone system supports an external music on hold source. This connects to the Audio port on the rear of the system's control unit. You can configure whether the input to this port is played to callers when they are put on hold.

The music on hold input can also be played to callers being transferred rather than ringing tone. That behaviour is controlled by the system's Ring on Transfer setting.

Status: Default = Active.
If enabled, the system will use the external music source connected to the phone system. If not enabled, the system provides a double beep tone repeated every 5 seconds.