[mythtv-users] sound channel settings changes

[Andy Wettstein]

On Tue, Apr 12, 2011 at 10:39:04AM +1000, Jean-Yves Avenard wrote:
> On 12 April 2011 05:39, Andy Wettstein <ajw1980 at gmail.com> wrote:
> > Hi,
> >
> > I'm running mythtv 0.24 from the debian multimedia archive.
> >
> > I'm using a gt240 with an HDMI connection to a sony receiver. For some
> > reason, I frequently see the sound setting change to stereo instead of 5.1.
> > It doesn't happen every time mythfrontend starts, and I haven't noticed a
> > pattern. This happens a couple of times a week though.
> >
> > Any ideas on why this would be happening?
> 
> The settings itself are set in the MySQL database and will never
> change unless you manually go into the settings and save the changes
> with the output set to stereo.
> 
> I'm not sure how old is the copy of the debian multimedia archive ;
> last time it was pretty old : still using the svn repository version.

The debian multimedia package is kept up to date pretty well. I'm
currently have version 0.24+fixes20110328-0.1 installed, but there is
0.24+fixes20110408-0.0 available.

> 
> The settings you've entered like 5.1 is ultimately just a hint that
> will be used by myth to know what to do if your hardware supports it.
> It will not try to use a setting if the hardware doesn't support it.
> 
> Say you configured myth with an audio card supporting 5.1 LPCM and you
> set audio output as 5.1.
> Now you restart mythfrontend but this time , it only finds an audio
> card supporting stereo.
> This is what myth will use: stereo.
> 
> You restart mythfrontend, this time you've put an audio card
> supporting 7.1 audio, it will use 5.1 because that's what you set in
> the settings.
> 
> Hope that makes sense.
> 
> I'm not sure what make you think that it changes from Stereo to 5.1.
> Is this when playback starts or when you go into the settings screen?
> For the value to change from 5.1 to Stereo by itself ; it can only
> happen if something modified the database.

The setting I am talking about is on the settings. I can tell that the 
setting has been changed because because during playback the receiver
will say PCM instead of Dolby Digital on shows that I know have Dolby
Digital.

I then go into the settings and find that the speaker configuration is
set to stereo. I change it to 5.1 and it works fine until the next time
it changes. As I said, it has changed to stereo several times and I 
haven't really noticed a pattern as to when it changes. I know it
doesn't happen every time mythfrontend starts or when the I have the
machine suspend because it doesn't happen every time that happens.