> I never have surround sound when watching DVD's though. Tried a couple
> of DVD drives, DVD software players, fiddled around withe the player's
> audio options, no luck.
You have two options. Either you get a player that can do "digital
pass-through"; ie, send the DVD disc's audio in its compressed form out the
back of your computer through a SPDIF output (SBLive Value has one; the
yellow connector at the back) and to your external decoder. You need an
audio cord with a phono-style connector in one end that you connect to the
Z680's coaxial digital input, and a 3.5mm mono male headphone-style
connector in the other to stick into your SBLive. There are adaptors
available that will transform a phono plug to 3.5mm; this is a much
easier/cheaper solution than trying to find a cable with these two different
types of connectors mounted on it directly. In PowerDVD, this is
accomplished by setting "SPDIF" as the speaker environment in the sound
section of the configuration panel.
The second option is to let your DVD software decode the audio and use the
soundcard's analog outputs to send the signals to the speakers. You need to
make sure the DVD software supports this, I use PowerDVD 5, and it works.
Note, DTS decoding usually does not come for free, so if you want to enjoy
these soundtracks it typically requires purchasing an extra audio pack.
Selecting "6 speakers" as the speaker environment accomplishes this (again,
using PowerDVD).
Note, I don't actually recommend PowerDVD, because even though it works NOW,
I did have some problems initially and their tech support is outsourced to
India and though very polite, is absolutely HORRIBLE AND USELESS. I might
just as well not have spent the time to write down my complaints at all, it
was that much a waste of time. Next time I need to update my DVD software, I
will look at WinDVD instead.
> A couple of e-mails are mentioning that using the digital only output
> (yellow hole in the back plus the checkbox in Windows)
You don't need to check that checkbox btw; all it does is disable the
regular analog outputs, nothing else.
> I can get digital output but stereo only, not surround.
> Digging further, I found that I might need a *stereo* minijack to RCA
> coax father cable to get the signal for more than two channels. Is this
> correct?
Well, yes and no.
SPDIF is only specified to carry two channels of audio; more will simply not
fit in the available bandwidth. That's why Dolby Digital and DTS are
compressed to squeeze more data into the available space. Getting a stereo
plug will not help you, as this design is a proprietary Creative thing only
made for some of their own speaker systems. There's no way to input two
SPDIF audio streams to your Logitech speakers and get them to re-combine the
audio signal for multichannel sound. Besides, you'd only get four-channel
audio that way anyway, not full 5.1.
> I also plan to buy an Audigy2 card for another machine. Do I need the
> same kind of gimmicks for that one too?
You need a phono to 3.5mm audio plug to use the SPDIF output, yes. And if
you buy an Audigy card, buy Audigy2 ZS, nothing else.

It rocks btw, very
nice sound and very low CPU consumption also.