I'm trying to get my Shuttle's nForce digital out to work, but it seems as if my system doesn't recognize that it has a digital out at all. (Analog out works fine)

I'm sure it's something fundamental (again :-/ ) but none of the research I've done has helped me figure out what I need to do.

The problem:

According to a few things I've read (including these thread...)

http://mysettopbox.tv/phpBB2/viewtopic.php?t=1621
http://www.gossamer-threads.com/lists/m ... sers/55133

...my nForce's analog and digital outs should show up if I do cat /proc/asound/pcm ..



I only get the first line when I do a cat /proc/asound/pcm . I want the "00-02" line, but I'm not getting it. (Don't care about the MIC line)

What I've Done:
* installed and ran gnome-alsamixer, tried turning on IEC958 options
* edited (successfully) my /etc/asoundrc based on this article:

http://www.mythtv.info/moin.cgi/DigitalSoundHowTo

* read the following posts...
http://mysettopbox.tv/phpBB2/viewtopic.php?t=1290
http://mysettopbox.tv/phpBB2/viewtopic.php?t=1653
http://mysettopbox.tv/phpBB2/viewtopic.php?t=1621

(this last one in particular... he wasn't able to get SPDIF to work, but at least he had the appropriate line present)

Thanks for any help.

OK, simple yes or no answer, since the deafening silence obviously means I've asked a stupid and/or redundant question:

Do I have to build a kernel and install ALSA from source in order to get SPDIF out to work (per this thread)?

well I think the silence is because your question is neither simple nor redundant. I personally have never tried to get digital sound to work, and many people haven't, and if they have it looks like you have looked at most all the info available.

oh and I fail to see what that thread in your second post has to do with alsa or sound at all.

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Xsecrets

I appreciate the reply, Xsecrets. It's good to know that this is not an easy nut to crack, therefore I'll move on to easier ones.

Re: that thread on recompiling the kernel. I read the following comment at ALSA's page on nForce:



I've never messed with CVS, so instead I DLed the most recent source I could find at alsa-project.org (1.0.5rc1) and tried to ./configure, and got:



Which is why I thought I needed a newer kernel, etc., which is why I linked to that thread.

I'm just flailing around here, basically, but I'm going to stop as I don't want to break a working machine. Thanks.

well you wouldn't have to recompile the kernel completely. basically the alsa modules want a configured source tree to compile. Just follow the first part of kernel recompile stuff. basically you have to untar the kernel source.

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Xsecrets

X, thanks for the tip on what alsa was asking for, because believe it or not (I sure don't, lemme tell ya), I have actually succeeded in getting digital out working with an nForce and MythTV.

I will try to write up what I did while it's still fresh and put it over in the Wiki HOWTO. Basically, I followed the steps described at the ALSA site for the nForce, and it seemed to work.

Now all I have to do is figure out the parameter to set in xine to get it to pass AC3 (as well as see if there's any way to get MythMusic to play through the optical out). It's always something.

what did you end up doing. I too have now gone through the process and compiled alsa. I followed those directions too. I think it may have to do with the .asoundrc file. What did you use and where did you put it?

I used the asoundrc file found here:

http://www.mythtv.info/moin.cgi/DigitalSoundHowTo

Use the one that's about halfway down the page, that's called "the 'I hope it's definitive' asoundrc file"

Although it should work in /home/mythtv/.asoundrc, I set it up globally by putting it in /etc/asound.conf

Make sure that the IEC958 settings are unmuted via alsamixer or gnome-alsamixer. After I made changes I did:



to store them (not sure if this was required).

Then go into MythTV front end. Go to Settings->General and change the audio setting from "/dev/dsp/" to "ALSA:digital"

Let me know if you get it going.

Do you get dolby digital (AC3) out of your spdif out when watching a DVD? My AV-receiver only tells me it's getting dolby digital [3/2] and switches on this nice blue dd led... but I can't hear dolby digital sound. SPDIF works with PCM stereo 48khz so I know spdif is generally working... just no dolby digital (AC3) over spdif...

I'm using the same .asoundrc and asound.conf!

Could it be, that AC3 streams from a DVD going through spdif (using the hwac3 option of mplayer) are being broken by something before it leaves to my AV-receiver and thus my AV-receiver has problems to decode it? How can I test / narrow this down? Are there AC3 5.1 encoded audio files somewhere I can test using aplay and to make sure it's not a mplayer issue.

Thanks for helping me. Getting dolby digital over spdif is the last issue I have...

I'm in the same boat, kinda. I'm trying to use xine and can't get it to use the spdif out yet. I haven't played with any of the audio setup settings, though, just tried adding things to the DVD Playback setup section of MythTV, which didn't work.

None of the videos I have in MythVideo have AC3 soundtracks, so don't have anything to check it with there, and of course regular TV doesn't have Dolby Digital either. So xine is my last issue too.

Hey there!

Well, I've gotten through just about every post here regarding s/pdif out on an nforce2 board and I feel like I'm this close! DVD's play with the AC3 full surround going out the optical s/pdif. MythMusic and MythVideo also play out of the optical. super cool!

Live and recorded TV is another story...

I've set audio output to:

ALSA:mixed-digital:0,2

and have tested this setting using:

And I do hear the sound coming into my stereo via the optical out.

Unfortunately, when I try live TV I get no audio and a message:


I've googled for this error and found nothing. Alsa seems to be working but I just cant figure out where this setting for Rate. coming up on four days now.

I've re-checked ~/.asound and /etc/sound.conf and I can't figure out where the trouble is... I tried muting everything using alsamixer, unmuting, combinations of mute and zero volume- nothing has worked.
thanks!

Asus a7n8x-vm/400
knoppmyth 15.1

why mixed digital tho? can't you pipe it directly with Alsa:digital? or Alsa:spdif?

http://www.knoppmythwiki.org/index.php? ... AudioHowTo

'digital' gives the same error, 'spdif' gives 'got 48000Hz' instead of 4000Hz with digital and mixed digital. Thanks for the response, the link provided is what got me to this point! googling the error returns very few clues.

Thanks again