after that last post i had a look around; "Cajun" is described somewhere as an app for turning your pc into a "massive audio jukebox". you can find it
here.
it can send audio to multiple "client" amps or whatever if you have a multi output soundcard.
this is the blurb from the website:
<snip>
CAJUN is a project to turn an old computer you might have kicking around into the centerpiece of your car or home audio system. CAJUN's features include:
Multiple stream support. If you have multiple sound cards in your computer, you can connect one to bedroom speakers, and one to your living room speakers. Each stream is separately controllable; i.e., each has its own set of keypads, infra-red controls, and LCD displays. (This feature is not likely to be useful in a car, unless you have a really long car :^)
Each stream has multi-device support, including: multiple input devices and multiple output devices (displays). Both the front seats and passengers in your minivan can see what's playing on their own display. All displays are updated at the same time.
All Displays can be any size - no limitations with multiple streams.
Display content is completely customizable. Different-sized displays can display different data.
Input and output devices may be connected and disconnected at any time. CAJUN continues to run.
Supports keypads, infra-red remote controls, LCD/VFD displays, FM cards, CD players, MPEG audio files, (WAV files+Ogg/Vorbis coming soon), Shoutcast/Icecast streams, etc.
An extension for invoking arbitrary Perl/Unix commands.
Easy-to-use, documented Perl API for writing new drivers.
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