[mythtv-users] BT Audio Tips?[Scanned]

[Bruce Markey]

Jason Keirstead wrote:
> I recently added a second tuner card to my myth box, without first thinking 
> ahead about how I was going to record the sound. I do not have an extra PCI 
> slot for another sound card, unfortunately.
> 
> I have tried over the past two days to get btaudio working, with no success.

http://www.mythtv.org/docs/mythtv-HOWTO-21.html#ss21.7

Not surprising. Most cards don't work with btaudio. Even if you
had a card that did work, btaudio imposes other limitations. You
are better off using a sound card whenever possible.
 
> When I modprobe it it does add new DSP devices for each of my two cards - 1 
> digital and 1 audio each, for a total of 4 new devices. I have tried 
> capturing from all of them with no real luck. Sometimes, when I capture on 
> the analog inputs I get incessant beeps, but no real sound.

I don't know how many hundreds of man hours have been wasted as
a result of this; the module will load whether or not the card
has an on-board DSP or is wired in a way that it can be used. I
believe the module will load even if there isn't a bttv card at
all.

> Has anyone had any real luck with btaudio? Any tips  for me?
> 
> My two cards are bt878, card 40 (STB TV PCI FM, Gateway P/N 6000704), and card 
> 42 (ProVideo PV951).

There are only three make/models that are known to have some
revisions that work (some revs of 401 don't).

These ain't then ;-).

> If I could just get btaudio to work for one card, I could use my sound card 
> for the other.

Yes but that's not gonna happen.

You said "sound card" and I don't know if that means built in to
the motherboard or in one of the PCI slots but you did say that you
have an open PCI slot.

My favorite configuration for a dual tuner is this. I use motherboards
with built-in audio. These are normally crappy and that's fine.
For normal stereo out I use a "SoundBlaster 16PCI" or for digital
out to a receiver I use a "SoundBlaster Live!". I use the SB card
as card-0 as the output device and for most things including plugging
in one of the tuner cards. I then configure the onboard audio device
as card-1, plug in the second tuner card, and set only its "Line" and
"Capture" items with "alsamixer -c 1". Even a crappy on-board chip
will do the simple job of recording from /dev/dsp1 well since it
isn't being used for output and there are no duplex issues or any
of that.

So, you only need one PCI slot for a sound card that you really like
(or can replace and upgrade) and the on-board audio is used for the
second DSP and nothing else. I've done this with three different
motherboards and it worked great every time.

--  bjm