[mythtv-users] All sound out S/PDIF

[David Snider]

Mark Knecht wrote:
>>>       
>> I recently just ran into this exact same issue.  I don't know why, but
>> after I upgraded to .21, (and alsa, and my kernel, and a bunch of stuff)
>> only the digital passthrough stuff worked.  I'm on gentoo and found a
>> file named /etc/asound.names.  In it I found device names that I didn't
>> see through the typical aplay -L.   One was named plug:spdif.  After
>> going through line by line on the names running aplay -D <name>
>> /usr/share/sounds/alsa/Noise.wav (an analog file).  I finally heard
>> sound when I used plug:spdif.  So, in MythFrontend, I changed the
>> default alsa device from ALSA:default to ALSA:plug:spdif and now
>> everything works perfectly.
>>     
> David,
>    I'd like to know more about this. I've been around alsa a long time
> and I've never heard of /etc/asound.names. I'm also a Gentoo user and
> none of my machines (8 in total) have this file so it being on your
> system is a surprise to me. I know of /etc/asound.state. Did you
> possibly mean that file?
>   
Nope, it's definetly /etc/asound.names.   This machine has historically 
had problems with the spdif out it's an ASUS M2NPV-VM.   In my 
troubleshooting steps, I actually updated to the 2.6.25 kernel and 
asound.names magically showed up.   I just checked my other system 
running 2.6.24 and it does NOT have the /etc/asound.names.  But I also 
had to put the ALSA;plug:spdif setting in the frontend.   Both of them 
are using the optical out directly to my receiver.

 From my 2.6.25 machine:
root at noir ~
# ls -l /etc/asound*
-rw-r--r-- 1 root root 2462 May 16 11:23 /etc/asound.names
-rw-r--r-- 1 root root 7833 May 16 10:53 /etc/asound.state

root at noir ~
# cat /etc/asound.names  
ctl {
        alsactl1 {
                name hw:0
                comment 'Physical Device - HDA NVidia at 0xfe024000 irq 20'
        }
        alsactl2 {
                name hw:1
                comment 'Physical Device - MPU-401 UART at 0x330, irq 10'
        }
}
pcm {
        alsactl1 {
                name default:0
                comment 'Abstract Device - Default Device (Duplex)'
        }
--snip--
        alsactl14 {
                name plug:surround71:0
                comment 'Abstract Device With Conversions - Front, Rear, 
Side, Center and Woofer (Duplex)'
        }
        alsactl15 {
                name spdif:0
                comment 'Abstract Device - S/PDIF (IEC958) Optical or 
Coaxial Wire (Playback)'
        }
Here is the entry-->        alsactl16 {
Here is the entry-->                name plug:spdif:0
Here is the entry-->                comment 'Abstract Device With 
Conversions - S/PDIF (IEC958) Optical or Coaxial Wire (Playback)'
Here is the entry-->        }
}
--snip--
}

Sun May 18 12:22:15 2008
root at noir ~
#

 From my 2.6.24 machine:
grigio ~ # ls -l /etc/asound*
-rw-r--r-- 1 root root 5210 Jul  1  2007 /etc/asound.state
-rw-r--r-- 1 root root 5262 Apr 22  2007 /etc/asound.state.20070422


>    I think the intended method to get a list of devices or PCMs is to
> use aplay -l or aplay -L
>
> mark at lightning ~ $ aplay -lL
> default:CARD=CK804
>     NVidia CK804, NVidia CK804
>     Default Audio Device
> front:CARD=CK804,DEV=0
>     NVidia CK804, NVidia CK804
>     Front speakers
> surround40:CARD=CK804,DEV=0
>     NVidia CK804, NVidia CK804
>     4.0 Surround output to Front and Rear speakers
> surround41:CARD=CK804,DEV=0
>     NVidia CK804, NVidia CK804
>     4.1 Surround output to Front, Rear and Subwoofer speakers
> surround50:CARD=CK804,DEV=0
>     NVidia CK804, NVidia CK804
>     5.0 Surround output to Front, Center and Rear speakers
> surround51:CARD=CK804,DEV=0
>     NVidia CK804, NVidia CK804
>     5.1 Surround output to Front, Center, Rear and Subwoofer speakers
> null
>     Discard all samples (playback) or generate zero samples (capture)
> default:CARD=DSP
>     Hammerfall DSP, RME Hammerfall HDSP 9652
>     Default Audio Device
> **** List of PLAYBACK Hardware Devices ****
> card 0: CK804 [NVidia CK804], device 0: Intel ICH [NVidia CK804]
>   Subdevices: 1/1
>   Subdevice #0: subdevice #0
> card 0: CK804 [NVidia CK804], device 2: Intel ICH - IEC958 [NVidia
> CK804 - IEC958]
>   Subdevices: 1/1
>   Subdevice #0: subdevice #0
> card 1: DSP [Hammerfall DSP], device 0: RME Hammerfall HDSP 9652 [RME
> Hammerfall HDSP 9652]
>   Subdevices: 1/1
>   Subdevice #0: subdevice #0
> mark at lightning ~ $
>
> However this doesn't show that my system has any PCMs so I'm very
> curious as to how we are getting different results. Have you set up a
> virtual device under Alsa and you're getting something that way?
>
> Thanks,
> Mark
>   
aplay -D <any name besides spdif:default> Noise.wav doesn't work.     
But, as you can see, when I run aplay -L on my 2.6.25 machine, I get no 
devices named plug:spdif

Sun May 18 12:25:20 2008
root at noir ~
# aplay -L
default:CARD=NVidia
    HDA NVidia, AD198x Analog
    Default Audio Device
front:CARD=NVidia,DEV=0
    HDA NVidia, AD198x Analog
    Front speakers
surround40:CARD=NVidia,DEV=0
    HDA NVidia, AD198x Analog
    4.0 Surround output to Front and Rear speakers
surround41:CARD=NVidia,DEV=0
    HDA NVidia, AD198x Analog
    4.1 Surround output to Front, Rear and Subwoofer speakers
surround50:CARD=NVidia,DEV=0
    HDA NVidia, AD198x Analog
    5.0 Surround output to Front, Center and Rear speakers
surround51:CARD=NVidia,DEV=0
    HDA NVidia, AD198x Analog
    5.1 Surround output to Front, Center, Rear and Subwoofer speakers
surround71:CARD=NVidia,DEV=0
    HDA NVidia, AD198x Analog
    7.1 Surround output to Front, Center, Side, Rear and Woofer speakers
null
    Discard all samples (playback) or generate zero samples (capture)

Sun May 18 12:25:23 2008
root at noir ~
#