I'm trying to find a way to send all audio from one Windows machine to
another across a local network. I have one laptop hooked up to the stereo,
but currently to use music players like Rhapsody or iTunes on it, I
have to run the apps on the remote laptop and control it remotely from
my main laptop. I'd like to be able to run the apps on this laptop,
but have all the sound be routed to the other laptop. Basically, I'd
just like this laptop to use the remote laptop as its soundcard.

I've done a lot of looking into this, and nothing has quite done the
trick. Any solution has to have good sound quality, as this is for
music, and can not be application-specific, meaning it will
work with Rhapsody, iTunes, Yahoo Music Engine, Winamp, etc. One issue
that raises is that it can't be tied to a particular format, like MP3.
It needs to also handle at least AAC and Windows Media files. Ideally,
it would just take the raw audio output that would normally go to the
soundcard.

You can put together a sort of pipe with a little configuration. First
of all, Open the full Volume Control, Options>Properties>Recording,
make sure Wave Out Mixed and/or Aux are checked. Press ok. Now click
the "Select" checkbox under Aux or "Wave Out Mixed" This will send all
output from the speakers just as a microphone or line-in.

You can then take a program like VLC (http://videolan.org,
http://forum.videolan.org/viewtopic.php?t=10049), File>Open Capture
Device, Select your sound card, check Stream Output, Settings...,
Check Audio Codec, choose MP3 or your favorite transit format and a
bitrate. Now look back up this page and check UDP. Then fill in the IP
address of the receiving computer (make up a port number, 1234 is
fine). You can Ok that Settings... dialog but wait on the main one.

Now start VLC on the receiving end, File>Open Network Stream>UDP/RDP.

Wallah. You should have a network bound conduit of sound. You can
automate the settings once you have them down to a shortcut with the
command line code at the top of the Settings... dialog.

It works! With the command line interface, it's quite slick and
simple. The only catch is that it still plays sound on this notebook
(the server). I was able to stop that by checking 'PC Spk Mute' in the
volume settings, but it would be nice if I could just mute it while
the VLC server is running, so the local sound starts up again as soon
as I stop the server. Any ideas?

Otherwise, it's good. There's a little bit of lag, but that's to be
expected. Also, I have to make sure the volume on this laptop is
turned pretty far down or the audio coming through the stereo is very
distorted. Not a big deal though.

It's funny--when I was trying to figure out a way to do this a few
weeks ago, I actually came across VLC, but for some reason thought it
couldn't do what I wanted. Anyway, thanks, you answered my question!