[mythtv-users] Cracking audio problem over HDMI ( really spdif with passthru )

mythtv at blandford.net mythtv at blandford.net
Tue Dec 22 01:47:38 UTC 2009

On 12/16/2009 11:02 PM, Allen Edwards wrote:
> On Wed, Dec 16, 2009 at 8:48 PM, mythtv at blandford.net
> <mailto:mythtv at blandford.net> <mythtv at blandford.net
> <mailto:mythtv at blandford.net>> wrote:
>     Hello,
>     I just purchased a new vizio 37 inch TV.
>     I really want to feed this tv over HDMI, so I also bought a fanless
>     9500GT card with 1GB.  I have connected the digital audio header on
>     the motherboard to the input on the video card.
> Please see the wiki I wrote and let me know if that helps or not
> http://www.mythtv.org/wiki?title=AllensDigitalAudioHowto
> <http://www.mythtv.org/wiki?title=AllensDigitalAudioHowto>Allen

Hi Allen,

Thanks for the response.  I have read through your wiki and think I am 
really close.

I have a few minutes to play with this again tonight.  Here is what I 
have now:

aplay -l
**** List of PLAYBACK Hardware Devices ****
card 0: Intel [HDA Intel], device 0: AD198x Analog [AD198x Analog]
   Subdevices: 1/1
   Subdevice #0: subdevice #0
card 0: Intel [HDA Intel], device 1: AD198x Digital [AD198x Digital]
   Subdevices: 1/1
   Subdevice #0: subdevice #0

more /etc/asound.conf
pcm.!default {
         type hw
         card 0
         device 1

Audio output device: ALSA:spdif - Default does not work for me I get no 
Passthrough output device: Default
Max Audio Channels: Stereo (MUST BE SET TO STEREO as of 6/2/2009 for 
passthrough to work)
Upmix: Passive
Enable AC3 to SPDIF passthrough checked
Enable DTS to SPDIF passthrough checked
Aggressive sound card buffering off
Use internal volume controls off

So other than the output device, I have matched your recommendation for 
the mythtv settings.

and the audio still sounds the same.  I am definitely getting audio, but 
it sounds like a bad reception on an old antenna.  it is crackly and 
maybe a like 'tinny'.

I really don't know what to try next.


More information about the mythtv-users mailing list