View Full Version : [SOLVED] No digital surround

May 13th, 2010, 06:02 PM
Hi people.

After some testing and error, I found that Ubuntu is unable to give me surround sound with SPDIF. I have an internal SPDIF cable from your sound card (internal) to a GeForce 9500 GT with HDMI out.

In sound options of Ubuntu 10.04 I have the option of selecting various analog surround setup (which after all is quite useless for me), and Digital Stereo (IEC958), no digital surround sound.

This has worked smoothly in Windows, but it seems that Ubuntu does not realize that the digital out is to send surround sound, not stereo.

Tested with a 5.1 AC3 file.
The result is that the left and right front delivers sound correct, the same with the center. However, when testing the rear speakers the sound is reproduced in the front left and right speaker.

Is it also possible to set up both analog output (internally, to stereo desktop speakers) and digital at the same time, so I do not have switch between them every time?

Analog stereo works fine btw.
With analog stereo selected I actually get stereo sound from my surround system as well as the desktop speakers, but I do not quite understand why.

~$ aplay -L
Playback/recording through the PulseAudio sound server
HDA NVidia, ALC888 Analog
Front speakers
HDA NVidia, ALC888 Analog
4.0 Surround output to Front and Rear speakers
HDA NVidia, ALC888 Analog
4.1 Surround output to Front, Rear and Subwoofer speakers
HDA NVidia, ALC888 Analog
5.0 Surround output to Front, Center and Rear speakers
HDA NVidia, ALC888 Analog
5.1 Surround output to Front, Center, Rear and Subwoofer speakers
HDA NVidia, ALC888 Analog
7.1 Surround output to Front, Center, Side, Rear and Woofer speakers
HDA NVidia, ALC888 Digital
IEC958 (S/PDIF) Digital Audio Output

May 13th, 2010, 06:16 PM
You might try these.

PulseAudio Fixes & System-Wide Equalizer Support

Make sound quality better in 2.5 Karmic

May 16th, 2010, 02:14 PM
Thank you, seems like I got a ltle bit further.
Still having trouble understanding it, but at least I have a place to start. :)

2hot6ft2's tip solved it. Surround is now awailable.
Marking the thread as solved.

July 25th, 2010, 10:42 PM
I have the same problem with digital outputs.
Running 10.04 fully updated, as well as the latest version of Pulse and the equalizer.
I've tried with 3 different sound cards and it is always the same, surround sound is ONLY available on analog outputs....:(

Any other ideas?