freeswitch/conf/autoload_configs/local_stream.conf.xml

<configuration name="local_stream.conf" description="stream files from local dir">
<directory name="moh_8000" path="$${base_dir}/sounds/music/8000">
  <param name="rate" value="8000"/>
  <param name="channels" value="1"/>
  <param name="interval" value="2"/>
  <param name="timer_name" value="soft"/>
</directory>
<directory name="moh_16000" path="$${base_dir}/sounds/music/16000">
  <param name="rate" value="16000"/>
  <param name="channels" value="1"/>
  <param name="interval" value="2"/>
  <param name="timer_name" value="soft"/>
</directory>
</configuration>