[mythtv-users] alsa 1.0.24, 0.24.2-fixes, ubuntu lucid, hdmi audio, AC3/DTS not working

[Jean-Yves Avenard]

Hi

On 22 February 2012 01:29, Steven Adeff <adeffs.mythtv at gmail.com> wrote:

> Like I said, I'm sure it can do this, as it worked with mplayer. For
> whatever reason the re-encoding that MythTV does internally does not
> apparently work however.

no... mplayer wouldn't have done so.. it would have passthrough the
original AC3 audio stream.

Here myth decoded it the AC3 stream, because you asked to do software
volume control (something mplayer won't do either).
As you've configured myth so it believes you have an amp supporting 6
channels LPCM, it doesn't try to re-encode the audio as AC3 and plays
the decoded 24 bits PCM audio instead.
This ensure that there's the least amount of audio quality loss.
Should myth had reencoded to AC3, there would have been loss of
quality there.

But as you still have provided what I (kindly I should add) asked in
regards to the ELD, we won't know for sure what your amp can really do
!

> we never did that, we only switched between the various HDMI inputs.
> As well, why would changing the output device cause the internal audio
> controls section to become enabled?

if you are referring to the software volume control, unless you
manually modified the settings, it won't change automatically, ever.

You did do something that modified it from 5.1 to stereo, and going
through the audio device can do that. Even going through the HDMI
device could do that depending on what ALSA drivers you are running.
With very recent alsa drivers, if there's nothing connected to that
hdmi device, it will be reported as stereo only.

In the mean time, I would appreciate if you posted the ELD information
I asked... Just to make sure the new 0.25 audio code will handle your
case properly.
Pretty please ????