How can I get SPDIF with ALSA?

[andefeldt]

Hi,

I've been searching and searching so many places. I found a lot of solutions, but none of them works for me. Well, here's my problem.

I have a Asus A8N-SLI motherboard (nForce4 chipset). I'm using the onboard soundcard. I'm not using the nForce drivers from NVidia, since they're OSS only. I'm running Ubuntu-5.10 with the stock alsa-drivers. Everything is fine except SPDIF - I can't make it work! I've connected my receiver with the coax output on my soundcard using a coax-cable. The sound works fine in Windows XP.

I don't have a .asoundrc file. I've checked the IEC958 settings in alsamixer, plus I've tried muting them, turning them all the way up, all the way down. If I play a song in eg. mplayer with:

mplayer test.mp3

the song is played in my monitor-speakers (my normal speakers). If I try:

mplayer -ao alsa:device=spdif test.mp3

I get no sound in my normal speakers, but also no sound is send to my receiver! Mplayer, however, plays the song without any errors (I just can't hear it).

What could be the problem? Any ideas?

If I can make the SPDIF work, is there then a way to get all sounds send to both the normal speakers AND the SPDIF?

Anders

[bwian]

Me too. :-(

[fhj52]

Okay, there's a little trick to it. Unfortunately for you et al I cannot give the specific setting but can tell you ALSA is pulling some, IMO, strange things: The AC97(IEC9whatever) is non-contiguous levels 0, 1, 2 ...
It looks like a some kind of volume control but it is not.
On my system(NV2200 & 2050 chipset), to get 5.1 SPDIF out, IIRC, I had to set the AC97 to 1.

Best thing to do is run
alsaconf
and let it configure everything (most likely there won't be sound... yet);
Then run
alsamixer
and set the PC SPEAKER and other volume controls to acceptable levels.
While there, try the first 'notch' for the IEC* as that might work on your system too.
IIRC, you have to restart alsa.

I that fails because the description is so bad, try Google and look for SPDIF and Mandrake. There is a post in the old MandrakeUser forum which provides basically the same info but in more detail.

Hope that helps...

c-ya

@andefeldt
BTW, I did the same thing you did: all the way down, all the way up, etc. It won't work that way. It's eiher the 'first' notch or 'third' notch, can't rem which. I cannot test here. My digital system is down so I have no connection for the onboard (digital) audio to use.