Getting TOSLINK to work

harksaw · 12-02-2009, 11:09 AM

I've just installed Slackware 13 and my sound card works with the analog jack but not the optical TOSLINK (IEC958)

I've been reading through here and have determined with "aplay -l" :

Code:

bash-3.1$ aplay -l
**** List of PLAYBACK Hardware Devices ****
card 1: ICE1724 [ICEnsemble ICE1724], device 0: ICE1724 [ICE1724]
  Subdevices: 1/1
  Subdevice #0: subdevice #0
card 1: ICE1724 [ICEnsemble ICE1724], device 1: ICE1724 IEC958 [ICE1724 IEC958]
  Subdevices: 1/1
  Subdevice #0: subdevice #0

that my digital output device is Card 1, Device 1.

If I go to VLC preferenes and set the ALSA output device to hw:1,1 I still have no TOSLINK output.

As the alsa page suggested, I tried editing my /etc/asound.conf file to add

Code:

pcm.!default {
        type hw
        card 1
        device 1
}

but this does not do anything. I'm out of ideas. It works in Windows and it worked in Ubuntu (but only with the most recent version), so I know it's not a hardware problem. Does anyone have any suggestions?

Woodsman · 12-02-2009, 02:45 PM

I think the first thing to consider is checking that in alsamixer none of the IEC958 inputs are muted. Then, check for the same thing in your desktop mixer (in KDE, KMix, for example). That might be all you need to do.

On the other hand, if I understand correctly, the optical connection represents a digital signal. Therefore the solution you seek might be similar to what I encountered trying to enable audio over HDMI. I emphasize the word similar,

so let anybody pipe in here to clarify. You can find a discussion of my journey here.

harksaw · 12-02-2009, 03:15 PM

Quote:

Originally Posted by Woodsman

I think the first thing to consider is checking that in alsamixer none of the IEC958 inputs are muted. Then, check for the same thing in your desktop mixer (in KDE, KMix, for example). That might be all you need to do.

On the other hand, if I understand correctly, the optical connection represents a digital signal. Therefore the solution you seek might be similar to what I encountered trying to enable audio over HDMI. I emphasize the word similar,

so let anybody pipe in here to clarify. You can find a discussion of my journey here.

Under alsa-mixer I have the following mixer bars for IEC958:

IEC958
IEC958 Output
IEC958 Playback
IEC958 1

Output just gives me the option of muting or not. Playback gives me four volume levels.

IEC958 and IEC958 1 don't let me select volume, but they let me select between the following choices:

PCM Out
H/WIn0
H/WIn1
IEC958 In L
IEC958 In R

None of these options get me any sound playing, although H/WIn0 and H/WIn1 give me a little bit of pop/hiss when the volume is turned way up whereas the others are completely silent.

But none of this gets me any music playing. I suspect this issue may be resolved with the newest version of ALSA (since my previous installation of Ubuntu did not have TOSLINK working until the most recent upgrade) so I am going to follow your path in the thread you linked and recompile my kernel with the newest version of ALSA.

octoberblu3 · 12-03-2009, 09:28 AM

One thing to check is running

iecset

and make sure the Data line says audio. If not, then run

iecset audio on

The only time that line should read something else is when you are passing raw AC3 or Dolby Digital to an audio receiver or similar device.

This, in addition to having the iec958's unmuted in alsamixer should be all you need to get sound from optical out. The volume of PCM sound is still controlled by the usual mixer sliders whether the output is analog jacks or digital outputs.

harksaw · 12-04-2009, 11:46 AM

Quote:

Originally Posted by octoberblu3

One thing to check is running

iecset

and make sure the Data line says audio. If not, then run

iecset audio on

The only time that line should read something else is when you are passing raw AC3 or Dolby Digital to an audio receiver or similar device.

This, in addition to having the iec958's unmuted in alsamixer should be all you need to get sound from optical out. The volume of PCM sound is still controlled by the usual mixer sliders whether the output is analog jacks or digital outputs.

When I enter "iecset" or "iecset audio on" I get the message:

"control "IEC958 Playback Default" (index -1) not found"

I'm not sure what that means. . .

edit: If I enter "iecset -c 1" it does say "Data: audio"

double edit: It is working now, at least in Amarok 2. I had been using VLC for all my testing (which I still can't get to work with TOSLINK) so I'm not sure exactly which step made it work, but it's working now.

harksaw · 12-04-2009, 08:34 PM

edit: never mind