Administrators can access up to 32 sources for music on hold. On Linux systems up to four USB sources are supported.
A music source can be a locally stored single WAV file (default) or a local directory of WAV files. You can configure playback to start every time from the beginning of the file or directory, or to start from where it left off the last time.
Alternate music sources can be located on Server Edition Primary, Secondary, and expansion systems. Server Edition also supports centralized music on hold, where the Primary Server streams music to the Secondary Server and all expansion servers.