[mythtv-users] Soundblaster live and AC3 for MythDVD help

[Paul Miller]

I've also been trying to get AC3 to work with my SB Live! Platinum 
(not 5.1).  It works perfectly in Windows and PowerDVD, so I know 
it's capable.  How are you executing xine or mplayer?  Is there a 
program to test AC3 without a DVD?  I created /etc/asound.conf based 
on yours and restarted alsa, yet I did not notice any differences.

I noticed that you have a couple more alsa control devices than I 
have..  Do I need to somehow enable my Live Drive II?
$ ls -1 /dev/snd
controlC0
hwC0D0
midiC0D0
pcmC0D0c
pcmC0D0p
pcmC0D1c
pcmC0D2c
pcmC0D2p
timer

If I execute mplayer (1.0-pre6-0.2) with
mplayer dvd:// -ao alsa:device=spdif -ac hwac3
my Yamaha receiver switches back and forth between PCM and Digital.  
It should say Digital if AC3 is working (both interfaces are actually 
digital).  I also noticed a message saying that "Sample format big 
endian AC3 not yet supported".

For xine (libxine1 1.0-1), I made the changes to my .xine/config file 
and didn't notice any difference than before any changes.  It outputs 
PCM only with the signal is significantly attenuated compared to 
mplayer, with no degradation in quality.

I'm using Debian/unstable with kernel 2.6.9 and alsa-base 1.0.7-2.

Any ideas?

Thanks!
-Paul

On Tuesday 04 January 2005 7:04 pm, Kyle Rose wrote:
> Gregg Farhat <3gemail at gmail.com> writes:
> > Okay.  I have an onboard sound card which is disabled, and the
> > sblive. The sound currently works through the SPDIF for mythtv
> > and mythvideo, but when I play a DVD I get static. I don't intend
> > to sound dumb, but I did not know how to handle the entrys with
> > multiples. Here is what I get from  lsmod | egrep snd
> >
> > snd_emu10k1            88521  1
> > snd_rawmidi              21733  1 snd_emu10k1
> > snd_pcm                   83529  1 snd_emu10k1
> > snd_timer                  25413  1 snd_pcm
> > snd_seq_device         6473  2 snd_emu10k1,snd_rawmidi
> > snd_ac97_codec        58821  1 snd_emu10k1
> > snd_page_alloc          8393  2 snd_emu10k1,snd_pcm
> > snd_util_mem            3521  1 snd_emu10k1
> > snd_hwdep                6597  1 snd_emu10k1
> > snd                           45477  10
> > snd_emu10k1,snd_rawmidi,snd_pcm,snd_timer,snd_s
> > eq_device,snd_ac97_codec,snd_util_mem,snd_hwdep
> > soundcore                 7713  1 snd
>
> So, for now I'd blacklist snd_seq_device, snd_rawmidi, and
> snd_hwdep. Here's what I have:
>
> snd_intel8x0
> snd_ac97_codec
> snd_pcm_oss
> snd_mixer_oss
> snd_pcm
> snd_timer
> snd
> snd_page_alloc
>
> Okay, so once you do this, here's my /etc/asound.conf (or
> .asoundrc):
>
> pcm.krose-dmix {
>   type dmix
>   ipc_key 3516
>   ipc_key_add_uid yes
>   slave {
>         pcm "hw:0,0"
>         period_time 0
>         period_size 1024
>         buffer_size 4096
>         rate 48000
>   }
> }
>
> pcm.dsp0 {
>   type plug
>   slave.pcm "krose-dmix"
> }
>
> ctl.mixer0 {
>   type hw
>   card 0
> }
>
> pcm.!default {
>   type plug
>   slave.pcm "krose-dmix"
> }
>
> I actually *only* have problems with AC3 output with mythtv, and
> only on the first attempt: all subsequent attempts succeed.  I have
> no problems with xine.  I'd just make sure you have the following
> lines in your .xine/config:
>
> audio.a52_pass_through:1
> audio.alsa_a52_device:iec958:AES0=0x6,AES1=0x82,AES2=0x0,AES3=0x2
> audio.alsa_mmap_enable:0
> audio.alsa_default_device:default
> audio.driver:alsa
>
> The alsa_a52_device line may be commented out; if so, you should be
> able to leave it as-is.
>
> Lemme know how this works.
>
> Cheers,
> Kyle