[mythtv-users] Audio over HDMI: my story

[Allen Edwards]

On Sat, May 2, 2009 at 11:10 AM, John Williamson <tyringham at gmail.com> wrote:
> On Wed, 2009-04-29 at 18:15 -0700, Allen Edwards wrote:
>>
>>
>> On Wed, Apr 29, 2009 at 1:27 PM, Jim Stichnoth <stichnot at gmail.com>
>> wrote:
>>         I thought you guys might enjoy reading this...
>>
>>         With my new Vizio HDTV, I decided to see if I could reduce
>>         cabling by
>>         using the HDMI-1 input (audio through HDMI) instead of HDMI-2
>>         (separate stereo audio input).  Everything worked until I
>>         tried
>>         playing a DVD rip, which gave no audio.  I figured it was a
>>         digital
>>         vs. analog audio issue, and I dug up all the discussions here,
>>         messed
>>         with alsamixer and so forth, but to no avail.  Finally I gave
>>         up and
>>         reverted to HDMI-2.
>>
>>         Later, I remembered that my nvidia card has only DVI output,
>>         not HDMI,
>>         and I was using a DVI<->HDMI cable for the hookup.  So, why
>>         was I
>>         getting any audio in the first place?  Wild.
>>
>>         Also, when I reverted to the original HDMI-2 TV input, I got
>>         no sound
>>         at all.  A sinking feeling of WAF-loss descended on me as I
>>         desperately messed with alsamixer and everything else I could
>>         think
>>         of.  Finally, I realized that I had swapped the TV's audio
>>         inputs from
>>         the myth box and the DVD player.  D'oh!
>>
>>         Jim
>>         _______________________________________________
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>>         mythtv-users at mythtv.org
>>         http://mythtv.org/cgi-bin/mailman/listinfo/mythtv-users
>>
>>
>>
>> The audio is on the same data stream as the video so the DVI-HDMI is
>> not the issue.  The issue would be that the video card would need to
>> get the sound from the sound card.
>>
>>
>> It is amazing how complex this stuff is.  Guess that is how people can
>> make a good living just hooking this stuff up for folks.
>>
>>
>> Allen
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>
>
>
> I had this issue with my recent build. The solution was to upgrade to
> alsa 1.0.19 and it all worked. I have always found sound utterly
> confusing in Linux so I used the script available here and it all worked
> perfectly
>
> http://ubuntuforums.org/showthread.php?p=6589810#post6589810
>
> I now have sound via HDMI. The only issue I have is that sometimes it
> starts to fluctuate in volume and I have to turn the TV off and on again
> and it works.
>
>
> John
>
>



This is the same script referenced in the wiki I posted at
http://www.mythtv.org/wiki?title=AllensDigitalAudioHowto

Just in case someone else finds this thread I wanted to reference that
as it answers many digital sound questions.  Glad to hear that what
you did was covered in the wiki even if you didn't find the wiki.

Allen