HDMI Sound Problems - Works Outside of MythTV

[Brett]

I have a motherboard with integrated nvidia HDMI that I would like to output both video and sound for an HTPC. With the help of the mythtv wiki and other forums, I managed to get my sound working through the HDMI output (outside of mythtv). The only thing I have to do to get the sound working is to enable the switch for "IEC958 1", or run the command

amixer set IEC958,1 on

After I do that, all sound works fine.

Now, I'm trying to get it working in mythtv and am having some problems.
I've tried using Allen's Digital Audio Howto (AllensDigitalAudioHowto - MythTV).

I've tried setting my /etc/asound.conf to all of the suggestions, but haven't been successful yet. The HDMI is card 0, device 3, so I got the following command to work:

mplayer -ao alsa:device=hw=0.3 -afm hwac3 test.mp3

My MythTV Settings are as follows:

Audio output device: ALSA:default
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

...but I have tried many other configurations / combinations. But it seems with four possibilities for the asound.conf file, eight or so possible combinations for the mythtv settings, I can't possibly try every one!



aplay -l gives:

**** List of PLAYBACK Hardware Devices ****
card 0: NVidia [HDA NVidia], device 0: ALC883 Analog [ALC883 Analog]
  Subdevices: 0/1
  Subdevice #0: subdevice #0
card 0: NVidia [HDA NVidia], device 1: ALC883 Digital [ALC883 Digital]
  Subdevices: 1/1
  Subdevice #0: subdevice #0
card 0: NVidia [HDA NVidia], device 3: NVIDIA HDMI [NVIDIA HDMI]
  Subdevices: 1/1
  Subdevice #0: subdevice #0

Any suggestions on how to proceed would be great.

[Brett]

I realized the hardware section may have been a better place for my thread below:

http://www.mythtvtalk.com/forum/inst...de-mythtv.html (Edit Coume: thread merged)

[Coume]

Mod:Threads merged

[CoreDump]

Is your HDMI plugged into a TV, or do you test it only with TV?

If so, disable passthrough, as most TV do not decode AC3/DTS on their HDMI input. Sad but true...

If not, I cannot help, on my 8400GS with spdif->HDMI, it works out of the box...

[AndyW]

Try setting Audio Output Device to

ALSA:plughw:HDMI,3

In your case ALSAlughw:0,3 will have the same effect, but using "HDMI" will protect against any device renumbering.

This makes the MythTV setting independent from the ALSA default.