BGM is a background music player primarly designed to act
as a music source, such as for music on hold, or background
music, for a telephone system using a standard sound card
and several optional music sources.
In addition to acting as a music source, bgm supports mixer
management and muting. Muting is used to allow a TTS pager
system (such as pagerd) to make pager announcements over
the muted background music, rather than by interrupting the
current
music source.