On Sat, 2012-07-21 at 13:43 -0500, Yfrwlf wrote: > Hello, > > I'm running Ubuntu 12.04 with two computers both with AMD video > chipsets. Both of the sinks I need to output sound on have no mode > setting in Gnome sound config. The analog outputs show surround options > available, but S/PDIF and HDMI options only offer stereo output. Is > there some way in which I can contribute to enhance Pulseaudio so that > future versions will have this corrected? S/PDIF is limited to two channels, unless you use some compressed format (AC3 or DTS). You can use those compressed formats if you set up the encoder plugins in the alsa configuration. PulseAudio uses the "a52" and "dca" alsa devices if they exist. It's not entirely clear to me what's missing from surround HDMI support. IIRC, there are some problems to be solved (I think help here would be much appreciated) before it can be supported, but on the other hand, the extra-hdmi.conf profile set configuration file (in /usr/share/pulseaudio/alsa-mixer/profile-sets) seems to already have definitions for 5.1 surround. default.conf doesn't have those definitions. extra-hdmi.conf is only used with NVidia and Intel chipsets. I think the purpose of extra-hdmi.conf is to expose all the 4 hdmi devices that those chipsets have, but I don't know why there's a difference in the surround handling. Maybe this is a bug, and default.conf should have the surround definition too? I hope someone more knowledgeable will clarify this. > On a separate topic, is there a way to force it to output with more > channels until a patch is applied? I've tried messing around with pacmd > and can't figure out how to set the channels. Does this need to be done > through editing one of the config files? The channel configurations are determined by the profile set configuration files, so familiarize yourself with the files in /usr/share/pulseaudio/alsa-mixer/profile-sets (or src/modules/alsa/mixer/profile-sets in the source tree). Some documentation is in default.conf and this wiki page: http://www.freedesktop.org/wiki/Software/PulseAudio/Backends/ALSA/Profiles -- Tanu
