[mythtv-users] HDMI and Audio Return Channel

[GZ]

On Sun, Sep 30, 2012 at 6:41 PM, Phill Edwards <philledwards at gmail.com> wrote:
> I have just bought a new HDMI cable which supports Audio Return
> Channel and I wanted to understand better what this will allow me to
> do.

Audio return channel is a feature that allows you to use the tuner
internal to the TV and have the audio routed "backwards" from the TV
to the home theater receiver.  It requires that you have a TV AND a
receiver that are connected via HDMI and both support ARC.  It's not
just a matter of the cable.
>
> 99% of the time I want to watch TV recordings and play the sound back
> through the TV speakers. That's what I've been doing to date with my
> existing DVI --> HDMI cable. But I also have an AV receiver and I'd
> like to set things up so that when I play a DVD from MythFrontend the
> sound plays through the receiver so that I get Dolby 5.1, DTS etc.
>
> Will this fancy new HDMI cable with Audio Return Channel allow me to
> do that somehow? If not, what's the best way of achieving that?

I'm not sure how you're routing your cables), but you really cannot do
this with ARC.  Basically, you should be routing the HDMI in the
following manner: mythbox ->receiver->TV.  You can sort of get this
behavior if you have a receiver that supports HDMI passthrough when
it's off.  Just run mythtv for TV with the receiver off.  Then, turn
the receiver on when you watch a DVD.  The problem is layering the
bitstreaming of DTS/dolby digital on that.  Often, the audio settings
for bistreaming to a receiver are different from the settings required
to get good audio from the receiver.  You may have to change the
frontend audio settings each time to make this work if your recordings
are dolby digital.  I have a similar setup and am mulling my options.
I believe that some people have a script that allows them to change
the audio settings, but I cannot find the link at the moment.
-Greg