Comment 35 for bug 348353

I have managed to incorporate the alsa config into my pulseaudio file now.
Adding the config to /usr/share/alsa/a52.conf and adding a hook into the pulse.conf within the same directory works perfectly.

My PPA now contains the packages and configs require to get this working from scratch.

So to do it:

1. sudo add-apt-repository ppa:danwood76/pulse-a52
(Adds my PPA to your software sources)

2. sudo apt-get update && sudo apt-get upgrade
(Updates package list and upgrades packages)

3. sudo alsa reload; pulseaudio -k
(Loads alsa config and restarts pulseaudio)

And you should then be able to select the 5.1 digital output in the sounds control panel.
I will test this on a live system once the packages have built.