I just purchased one of these cards from ebay specifically to play HD audio through the DVI port of my TV.
No need for the Creative Sound Blaster Digital I/O Module at all to do this – all it takes is a mono (preferably) or stereo 3.5mm headphone plug, the header plug from a motherboard’s LED with wire attached and a little soldering.
If you are using a mono 3.5mm headphone adapter connect each wire as follows (there will only be one core and one shield):

If you are using a stereo 3.5mm headphone adapter connect each wire as follows:

Connect the 3.5mm plug to the white port of the sound card (labelled digital IO) and the jumper header to the 2 pin socket on the soundcard.
You may need to turn the jumper header around 180 degrees to get the audio working – one pin is digital audio in and the other is digital audio ground.
In the sound control panel you need to enable digital I/O or “Audigy Analog/Digital Output Jack” and disable “IEC958 Optical Raw”.
Edit for ubuntu Karmic Koala 9.10:
You will need to install alsamixer so you can toggle the options:
$ sudo apt-get install alsamixer
$ alsamixer
Use the cursor keys to select the options:
“IEC958 Optical Raw” – press ‘M’ so the display shows ‘MM’
“Audigy Analog/Digital Output Jack” – press ‘M’ so the display shows ‘OO’
Finally press Escape to exit the program.
Mail me if this helps you, it’s nice to know I have been useful 
labby.co.uk has catchall mail, so anything sent to any address at that domain will reach me