[mythtv-users] Dual tuners - how does the sound work?

[Phill Edwards]

I currently have a bt878 chip tuner card and I want to buy a 2nd one
but I don't understand how the sound recording can possibly work on
this setup. From what I understand at the moment, the sound gets
recorded by connecting a lead from the sound out from the tuner card
to the line in of the sound card (which in my case is  on-board). If
that lead is not connected in this way then I'll get a video recording
with no sound. Am I right so far?

So, when I put a 2nd tuner card in how do I connect the sound out to
the line in of the sound card when it's already been taken up by the
1st tuner card? Is this when you need btaudio? I believe not all tuner
cards support btaudio. How can I determine which do and which don't -
from what I've seen it seems to just be some Hauppauges and WinTV
Radio?

Are my options as follows:

1) Buy a sound card when I buy a tuner card, OR
2) Buy a tuner card that supports btaudio (very limited choice and
expensive, I believe)

Lastly, my mobo has a S/PDIF connector which I currently have no idea
how to use but I do want to get Dolby digital working in the future
for DVD playback. Does this have any bearing on what sort of sound
card I should buy if I go for option 2?

Regards,
Phill