Music on hold (MOH) is a common feature of modern phone systems. FreeSWITCH allows you to have many different MOH selections.
You will need some music files if you wish to customize the MOH. Also, if you have MP3 files that you would like to use for MOH, then you will need a utility that can convert them into standard WAV files. A freely available tool can be found at http://www.mpg123.de. You will also need a text editor and a telephone connected to your FreeSWITCH server.
The first thing to do is to install the default MOH files from the FreeSWITCH download site. Linux/Unix users can issue the following command from the FreeSWITCH source directory:
make cd-moh-install
On Windows, the sound files are installed automatically as part of the MSVC solution file.
Once the sounds are installed, you can confirm that they work by dialing 9664 (no reloadxml or system restart is necessary).