GSI is an easy to use audio system which can be used over a network and which gives applications, through a very simple API, sample playing with stereo, 3D, doppler effects, music playing (MIDI, HMP, MUS), cd playing and ejecting/changing. GSI also contains a separately usable sound/music loading/saving/format conversion library libgsif (au/aiff/voc/wav/raw, midi/hmp/mus).
GStreamer is a library that allows the construction of graphs of media-handling components, ranging from simple Ogg/Vorbis playback to complex audio (mixing) and video (non-linear editing) processing. Applications can take advantage of advances in codec and filter technology transparently. Developers can add new codecs and filters by writing a simple plugin with a clean, generic interface.
Helix DNA Client
Helix DNA Client the media playback engine used by the RealOne Player. It contains standards-compliant H.263 and MP3 decoders, RealAudio and RealVideo binaries, and sample user interfaces.
The Network Audio System is a network transparent, client/server audio transport system. It can be described as the audio equivalent of an X server.
NetStreamer is a streaming application to be used over 24+ kbit/s networks, like LAN's and ISDN. At the moment there are a linux / x86 ELF binary version and a source version available, under the GNU General Public Licence. NetStreamer offers the possibility to distribute live Audio over network, like Music from internal CD-ROMs or a radio signal on the line-input of a PC.
Real Rekord is a KDE program which helps you record streams from Real Player using GNU/Linux. It lets you record realaudio/realplayer streams by using vsound 0.5 (sits between program and /dev/dsp) and sox (converts audio file formats).
rplay is a flexible network audio system that allows sounds to be played to and from local and remote Unix systems.