ALSA not working with 5.1 SPDIF

**Purshottam Y** · 19-01-2011

I have my openSUSE 11.3 is a Creative X-Fi USB connected. At the X-Fi is a vicious directly E100 5.1 sound system via RCA 6x, without SPDIF / Opt / Coax. The sound itself works, but only with stereo, front only front L and R are having the sound. Whether VLC, Mplayer, Kaffeine, the OS itself, or games, all just 2 channels (all audio configurations have all been tried out). VLC and MPlayer have also launched direct with surround 5.1 but still it is not working.

The only exception: If I do a test ALSA directly and specify that it is 6 channels involved, this works correctly with 5.1:

speaker-test-c6-Dplug: surround51-t wav-l1

The way I understand it, all 5.1 Surround configurations for SPDIF-intended and not directly analogous. The same applies to all asound.conf 's that I have found. How to configure my ALSA (or the app's) so that it uses 5.1 analog without SPDIF?

**Aanand** · 19-01-2011

Most DVDs and several additional files have surround sound. MPlayer sustains surround playback but does not activated by default for the reason that stereo equipment is far more common. To play a file that has extra than two audio channels, utilizes the-channels. In order to play a DVD with 5.1 audio, such as:

mplayer dvd: / / 1-channels 6

Note that this is despite the name "5.1" to six discrete channels. If you are suitably equipped for surround sound have any, and it is safe to select channels in the MPlayer configuration file ~ / .mplayer config /. For example, quadraphonic playback the default, add the following line:

channels = 4

MPlayer audio in four channels then output when all four channels available.

**Aienstaien** · 19-01-2011

DVDs usually have surround audio encoded in AC3 (Dolby Digital) or DTS (Digital Theater System). Some modern audio equipment is capable of internally decoding these formats. MPlayer can be configured to route the audio data without decoding them. This will make some effort only if you have a S / PDIF (Sony / Philips Digital Interface) jack on your sound card. If your audio equipment can decode both AC3 and DTS, it is safe to enable passthrough for both formats. Otherwise you should pass-through only for the format, activate your equipment supports. Pass through the command line to enable:

For AC3 only, use-ac hwac3
For DTS only, use-ac hwdts
AC3 and DTS, use-afm hwac3

Pass-through in the MPlayer configuration file:

For AC3 only, use ac = hwac3,
For DTS only, use ac = hwdts,
AC3 and DTS, use afm = hwac3

Note that at the end of ac = hwac3, and ac = hwdts, a comma (",") is. This will ensure that MPlayer other codecs drawing on which it usually used when a file is AC3 or DTS audio does not have ;. Afm = hwac3 does not need a comma MPlayer anyway, others fall back on when an audio family is specified.

**Shutdown** · 19-01-2011

As the speaker test was successful, it may not be due to ALSA.

Do you have a sound server somewhere in between? Set Mplayer when the option "-ao alsa" to direct the sound card output. The audio stream is chosen to by-Mplayer from aid. I would like to suggest you to check the aid-values in the log. If still you are getting the problem, then feel free to post here. Also it would be better for us to troubleshoot, if you provide your log.