>And/or can anyone suggest how best to stream radio on my network with a digital radio tuner (has digital out), my linux server and a bunch of Rio Receivers on the network? I'm not really sure where to start.

I'm guessing
1) the tuner is USB
2) you can use it on your linux box already
Well the rio is a linux box too. If it only had a USB port, you could run the same software (command line to start with).

Start with the Linux USB developers site.

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I don't like the shoutcast solution sugested. Instead how about:


1) If anyone already has a linux way to share USB radio over ethernet it will work for you.


2)The radio is probably spittling out already fully decoded audio for AC97, (Shoutcast is mp3 encoded (i think), the rio decodes it into what the radio is already spitting out then plays it)

a) the rio needs a linux wav player (which exist)
b) Your linux box needs to suck in the usb stream and resend in as an ethernet stream (propbably simple in perl)
c) a ui on the rio to talk to the linux box which then talks to the radio (so you can change channels)

3)
some magic hardware to let the rio talk USB, and the standard linux usb driver for your radio.

However all the ethernet/USB adapters I've seen are
USB host <-> (converter usb client<->ethernet) <-> ethernet
and you need
USB client <-> (converter usb host<->ethernet) <-> ethernet


but I could be worng there, Again the Linux USB developers site is the place.