[mythtv-users] Missing Dolby Digital Audio Stream, HD2000/DVB/AC3

[John Freer]

Hi All:

For a number of weeks now, I've been enjoying my HD2000 card with the
DVB driver.  When using the card, my Yamaha receiver would click into
"Dolby Digital" mode and I'd have 5.1 channels of audio.

Unfortunately, after I installed the latest -108 version of the
mythtv packages today, dumped my database, and re-loaded / scanned
the transports, I don't get "Dolby Digital" to light up on the
receiver anymore, sort of.

Some points: 

1.  When watching local ATSC, my Yamaha AV receiver, within its
on-screen display, says that it is receiving a "Dolby Digital"
stream, but the text on the front display says "Pro Logic".  I
definitely only get 2-channel audio.

2.  I used to get 5.1 DD audio on this channel.

3.  When I play a DVD from mythdvd with the -ac hwac3, option, it
lights up as "Dolby Digital" and I get 5.1 channel audio.  No changes
at all to the receiver to get this.  Just fired up mythdvd and hit
play.

4.  I've tried to use the "+" key to change to a different
subchannel.  This yielded no result.

5.  I've tried changing the "Send AC3 audio to external amp" option
in general setup.  When I have it enabled, the Yamaha amp OSD says
"Dolby Digital", but still it is only pro logic 2 channel sound. 
When I have it disabled, the Yamaha OSD says "PCM".  So, I think this
is working right.

OK:  So, what are the chances that the 5.1 DD stream was not properly
scanned / is not being used?  My working theory is that myth is only
selecting a 2-channel audio stream rather than the 5.1 one.  Still
encoded in DD, but only 2-channel, which confuses my receiver.


Any thoughts would be helpful.

Thanks,
JF