SPDIF output is 2-channel PCM only. To get 5.1 output you need to send your receiver a passthrough AC3 or DTS stream, or enable Dolby ProLogic II on your receiver to simulate the surround effect. You won't get the system to send 6 channels of raw PCM via S/PDIF, it's only capable of surround when a digitally encoded compressed stream (AC3/DTS) is passing through, due to bandwidth restrictions of the optical signal. That's what I've been led to believe on my own journey to get a similar system working over here on an AD1986a. Best of luck, Steve On Feb 19, 2009, at 3:07 PM, brashquido@xxxxxxxxxxxxxx wrote: > Hi All, > > I've installed ALSA 1.0.19 on a fresh install of Mythbuntu 8.10 on two > seperate machines, and I am trying to get digital audio pass through > to > work properly. One machine with an ALC888 soundcard with SPDIF > output, and > the other with a VT1708B soundcard with HDMI output. I have digital > output > working using the mplayer "-ao alsa:device=spdif" or "-ao > alsa:device=hdmi" > commands respectively, and the Dolby Digital and DTS indicators > light up on > my receiver that it is getting a valid digital audio stream. > Ultimately I > know it works as I can hear the audio tracks in my movies. > > The problem I am having is that I only seem to be getting 2 channels > on > both machines, and not only in mplayer as I've tested using speaker- > test > and also MythDVD. Both these cards are capable of 7.1 sound, but > ultimately > I need to configure them to output 5.1 (as that is all the receivers > they > are being connected to are capable of). I've scoured the Internet, but > don't seem to be able to find any information on configuring the > number of > channels for SPDIF output. Can someone please help me? > > > > ------------------------------------------------------------------------------ > Open Source Business Conference (OSBC), March 24-25, 2009, San > Francisco, CA > -OSBC tackles the biggest issue in open source: Open Sourcing the > Enterprise > -Strategies to boost innovation and cut costs with open source > participation > -Receive a $600 discount off the registration fee with the source > code: SFAD > http://p.sf.net/sfu/XcvMzF8H > _______________________________________________ > Alsa-user mailing list > Alsa-user@xxxxxxxxxxxxxxxxxxxxx > https://lists.sourceforge.net/lists/listinfo/alsa-user ------------------------------------------------------------------------------ Open Source Business Conference (OSBC), March 24-25, 2009, San Francisco, CA -OSBC tackles the biggest issue in open source: Open Sourcing the Enterprise -Strategies to boost innovation and cut costs with open source participation -Receive a $600 discount off the registration fee with the source code: SFAD http://p.sf.net/sfu/XcvMzF8H _______________________________________________ Alsa-user mailing list Alsa-user@xxxxxxxxxxxxxxxxxxxxx https://lists.sourceforge.net/lists/listinfo/alsa-user
