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I upgraded to VLC 2.0.0 over 1.1.13, but now I cannot get VLC to output 5.1 audio (or anything more than stereo). In 1.1.13 (and earlier), selecting my surround51 device (or whatever it was labeled...cannot remember) correctly played 5.1, no problem. Now, selecting the equivalent 5.1 device (HDA ATI SB, ALC889A Analog 5.1 Surround output to Front, Center, Rear and Subwoofer speakers (surround51:CARD=SB,DEV=0)) has seemingly no effect at all, either when changing to it explicitly from the default stereo or selecting it as the default device in VLC's preferences. I've tried playing regular video files with 5.1 audio and a 5.1 audio test file, but I get stereo only (which is spread over all speakers, rear included -- left side audio plays on left front&rear and centre, similarly for right). mplayer still outputs 6 channels when specifying surround51 as the device, and ALSA's speaker test works fine as well. I'll share some debugging output when running with `vlc -vvv`: Note the "remixing from 6 to 2 channels" line, which turns up absolutely nothing useful on Google (or here). I'm on Slackware 13.37 using AlienBob's package. I have had no trouble with his statically linked pre-2.0 packages. In retrospect I should have saved a copy of his older package in case something went wrong...I just didn't expect any trouble with VLC.

I'd appreciate any help and would of course provide any more information that may be needed.

I compiled VLC 1.1.13 using the same build script that was used for the 2.0.0 package and 5.1 audio is working again. I don't know what's wrong with the ALSA output with VLC 2.0.0 on my system, but since I have a working (albeit now outdated) VLC package I suppose all is well for now. I have to assume this is a bug (especially since the ALSA stuff was reworked between 1.1.13 and 2.0.0) but either I'm the only one with this problem, I'm the only one using 5.1 analog audio, not enough people have upgraded to 2.0.0 to notice, or no one else has bothered to chime in.

same problem here. 5.1 isnt working and spdif neither. when i start a52 files with --spdif it gives me this:

[0x7f9354000958] main audio output error: conversion pipeline failed: a52 -> a52
[0x7f9354000958] main audio output error: cannot setup filtering pipeline
[0x7f936ceba3f8] main decoder error: failed to create audio output

or with dts files:

[0x7f4384000958] main audio output error: conversion pipeline failed: dts -> dts
[0x7f4384000958] main audio output error: cannot setup filtering pipeline
[0x7f43b0c10208] main decoder error: failed to create audio output

but when i change to "creative x-fi, iec958 non-audio iec958 (s/pdif) digital audio output" manually, spdif works but still only stereo output.

i have arch64 and i also had no problems pre vlc 2.0.
help would be appreciated.

thanks in advance.

Unfortunately ALSA is really --please stay polite-- up. Here the logs show that your "surround51" cards will accept any number of channels from 2 to 8. This makes no sense; it should obviously only accept 6 channels. In fact, it works fine for me (surround51 only accept 6 channels here). I don't know if it's a bug in ALSA for your audio card, or a just a bug in VLC.

VLC tries to second guess ALSA: Where stereo is accepted, it assumes that stereo is wanted. That is historical: most cards are wired with stereo speakers.

The simplest solution is yet to use PulseAudio, that does not suffer from ALSA's design deficiencies.

This is fixed in VLC 2.0.1. You can now configure the VLC/ALSA plugin explicitly to 5.1. Also S/PDIF should be fixed.

Sorry for taking so long to respond. I just tried VLC 2.0.1 and it seems to work perfectly (after explicitly setting the channels in the preferences). I really appreciate your efforts to supply a workaround even if it was an ALSA-derived problem.

Thanks!

Hi, I'm suffering from the same problem (or at least one that is related), and for me, it is not fixed. The version I'm using is VLC 2.0.3.

In my audio setup, the DD5.1 receiver is connected to the digital output of the sound card and I use it both for stereo (music, moviez, etc.) and for 5.1 sound (in movies), for which I have to use the passthrough.
This worked perfectly for vlc, I could select the digital audio output for audio passthrough in case I need it and keep stereo otherwise. Since vlc 2.0.0, this changed and does not work anymore.

I can still use the passthrough, when I select the option "Use S/PDIF when available", but only once. With that I mean, that it works fine when I first start a movie, but switching to another audio channel or another device will just result in no sound output at all. It is also very inflexible, since I don't want to use the S/PDIF in every possible case.
When not using this option, I don't get S/PDIF passthrough at all anymore, just stereo, in all cases. If I force the alsa detection to 5.1, then I don't get sound at all (and this would be the wrong thing for me anyway).

I don't really know what changed between vlc-1.1.11 and vlc-2.0.0, where it worked perfectly with the former and does not work at all with the latter.