Steam + ALSA A52 (Dolby Digital) plugin. Possible

[PayneToTheMax]

Has anybody tried this? Would be great for people with HTPCs with S/PDIF based audio.

[ripper81]

In theory this should work if pasthrough for dolby digital (AC3) is enabled in pulseaudio. To do this you have to install the pulseaudiomixer pavucontrol because most of the other audiomixing tools for linux dont show this options. After dooing a system reboot things should work as insisted.

If you are using a distribution without pulseaudio (plain ALSA) this should work without further configuration.

In both cases you have to make shure that the right sounddevice is enabled in your audiomixer and in the steam settings. It should be named S/PDIF or IEC958 digital stereo. Don't use shown sounddevices that are labled as surround 5.1 devices. These are for users that want to decode dolby digital internaly for playback over an analog 5.1 speakersystem.

This should also work for HTPCs with HDMI intefrace.

I have configured my HTPC this way and it works great with kodi mediacenter. However the games i own are only delivering stereo sound. It seems that the sound is downmixed to stereo for all the games. Most games doesn't seem to support other soundformats than stereo at least not on linux.

[PayneToTheMax]

That's not what I really meant. AC3 passthrough is great, and I'm also using it with Kodi, however, it only works when there is an AC3 source - that is not the case with videogames. That's why I'm thinking maybe it's possible to make Steam work with real-time AC3 encoding, like A52 plugin for ALSA. I tried it on my Ubuntu setup, and it generally works, except when I have to make Steam work with it, Steam Big Picture crashes, presumably because of the necessary changes made to Pulse and ALSA (samplerate change from 44.1 to 48khz).
I was thinking it could work with Steam In-Home Streaming, because Steam on Linux supports 6 channel PCM output through HDMI, and converting 6 channel PCM to 6 channel AC3 is exactly what that ALSA plugin is supposed to do.

Here's the page I was following: https://help.ubuntu.com/community/DigitalAC-3Pulseaudio

[Letalis Sonus]

Remember that all ALSA plugins you're using also have to be available as 32bit on 64bit systems.