XBMC and 5.1 pass-through audio (?)

[Ronald F. Guilmette]

I've just installed the current official xbmc-11.0_6 port on my laptop
(which uses an Intel GS45/4500MHD/ICH9M-SFF chipset) under FreeBSD 9.1-RC2.

In general, and ignoring the fact that it is slow as pig unless run as root
(a problem for which I have already filed a formal PR) xbmc runs adequately
well and produces good output out of the laptop's HDMI port.  An HDMI cable
runs from the laptop down to my Sony STR-DH520 AV receiver which is, in turn,
wired via HDMI to my flatscreen, and to 4 speakers (front-left, front-right,
back-left, back-right).

Video is OK.  The problem is audio.

Earlier, I was able to take the surround-sound test file available here:

   http://www.tfm.ro/win32-projects/test-avi-ac3/

and using (with minor adaptations to my partciular setup) the instructions
provided here:

  http://aksyom.blogspot.com/2010/08/surround-sound-with-freebsd-8x-and.html

together with those on this page:

   http://www.mplayerhq.hu/DOCS/HTML/en/advaudio-surround.html

and then I was able to get nice Dolby Digital 5.1 encoded audio out of my
laptop's HDMI port and down to my DD capable AV receiver.  This all works.

Now, with that small bit of success under my belt, I am moving on and would
like to get xbmc running under 9.1-RC2 with the same pass-through of
encoded 5.1 audio, out of the laptop's HDMI port and down to my AV receiver.

Can anyone here provide me with any guidance on how to accomplish this
trick?

So far, I am easily able to get xbmc to send two-channel LPCM audio down
the HDMI pipe to the receiver, but unlike in the case of mplayer, I have
no idea how to properly configure xbmc to send 5.1 channel Dolby Digital
down to the receiver (and so far, the things I have tried haven't worked).

Any help would be appreciated.


Regards,
rfg