Has anyone got surround sound working on an EPIA with VT1616?

I have used the audio out (stereo) plug, but in theory I should be able to either

a) enable "smart 5.1" whereby the 3 audio plugs in the back
(mic, sound out, sound in) become 5.1 outputs, or
b) enable SPDIF and have digital audio goodness flowing to my
amp.

I have tried b), and do indeed have SPDIF going to my amp,
but it seems to only be stereo and not 5.1.
I can't find how to do a) inside linux.

My question is: has anyone got surround going with an EPIA board?
If so, what's the magic incarnation.

Thanks
Tuatara

Turns out that xine doesn't seem to like people fooling with its ~/.xine/config file (setting 'Pass Through'), especially while its running.

When I did that, my sound got really messed up.

So I upped my config UI to 'Advanced' and ran xine config from within xine itself. That fixed the problem and now I have 6 georgeous channels over a digital SPDIF cable to my AMP.

Ok: here's what you need to do to get surround sound working on an EPIA via SPDIF.

Note that you actually have several problems to solve:
a) xine playing 5.1 content *and* stereo content
b) mythmusic
c) mythtv.

First off:
- Enable SPDIF output by setting the jumper oyour motherboard.
- Then run
amixer set "IEC958 Playback AC97-SPSA" 0

Now setting up MythTV:
- go to setup -> general.
- Turn on ac3 passthrough.
- Turn off your mixer.
- Set your audio device to be "ALSA:spdif". Yes, thats not one of the options, but you can just type it in.

For MythMusic
- go to setup -> music
- set audio device to be "ALSA:spdif". Same comment as above.

For Xine (thanks to: http://www.flaterco.com/kb/audio.html)
- right click -> Settings -> Setup.
Gui tab: set Configuration experience level to Advanced or higher.

Audio tab:
o Set device used for mono output (device.alsa_default_device) to iec958.
o Set device used for stereo output (device.alsa_front_device) to iec958.
o Set device used for 5.1-channel output (device.alsa_passthrough_device) to iec958.
o Ignore the other "device used for 5.1-channel output" (device.alsa_surround51_device).
o Set speaker arrangement to Pass Through.