[mythtv-users] SPDIF output works for MythMusic, but not MythTV

[Michael Haan]

Did you ever find a solution to this?  I'm getting the same exact
thing.  Command-line playing works fine over spdif, myth dvd works
fine, playing recorded shows works fine.  Watching live tv does not.


On Fri, 18 Mar 2005 16:35:31 -0500, Brad Benson <bbenso1 at gmail.com> wrote:
> On Fri, 18 Mar 2005 14:48:15 -0600, Andrew Close <aclose at gmail.com> wrote:
> 
> > you can buy a male to male stereo patch cable and plug one end into
> > the output of your pvr-350 and the other into the input of your sound
> > card.  when you listen to music it will be the same as usual.  when
> > you watch tv you should now get sound out of the SPDIF port.
> > not pretty, but it should work.
> 
> I've got a related problem and it's been driving me nuts for quite a
> while now.  I have a pvr350 and a zoltrix nightingale soundcard
> (c-media CM8738 using cmpci kernel module).  I have the 350 audio
> outputs linked into the line in of the soundcard and both spdif
> optical and stereo rca connections from the soundcard outputs to my
> receiver's inputs.  I've tried the instructions in the
> DigitalSoundHowTo on mythtv.info that say to set "Analog to IEC958
> Output" to on in alsamxer.  The problem is that alsamixer has a
> setting labeled just IEC958 Output which seems to have no effect
> whether it is on or off.  There is another setting labeled IEC958
> Loop.  My understanding of this setting is that it pipes the analog
> input back out through the spdif output.  However, when I enable this
> setting I am very clearly getting analog audio coming into the
> receiver, but sound works for all parts of myth.  (I know this because
> I can disconnect the spdif cable and still get sound, but when I
> disconnect the analog cables sound goes away.)  When I disable this
> setting I get audio over the spdif connector for MythMusic, MythVideo,
> MythDVD, etc.  Everything EXCEPT tv.  The only way I've found so far
> to get sound from tv over the spdif connector is to use the
> instructions from the DigitalSoundHowTo for Via sound chips.  The
> problem there is that the only way to get that to work is to issue
> this command from the command line:
> 
> arecord -D hw:0,0 -fdat | aplay -D mixed-digital
> 
> This works perfectly for outputting tv audio over the spdif connector,
> but there is no way to automatically execute that command every time
> myth plays a recording and if I leave that command running all the
> time I get double audio from all other parts of myth (music, video,
> etc).
> 
> Has anyone else had a similar problem?  Is anyone else using a cmpci
> sound device succesfully using spdif output for all parts of myth?
> The sound quality I get over spdif is obviously much better than the
> analog connections, but right now I'm stuck using analog for
> everything in order to avoid having to switch audio inputs when using
> different parts of myth (because that's too much for the GF to handle
> ;).
> 
> Thanks,
> Brad
> _______________________________________________
> mythtv-users mailing list
> mythtv-users at mythtv.org
> http://mythtv.org/cgi-bin/mailman/listinfo/mythtv-users
>