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Using VLC 1.2.0-git Twoflower compiled abuild on messiah (Jun 30 2011 10:30:18) on openSUSE 11.3/Gnome. With certain AVI files, speech is barely audible even with the sound volume maxed out (both vlc own and system volume control), while music/sound effects are OK. Ctrl+I shows that the files have A52 (aka AC3) audio codec, channels 3F2R/LFE.

In Audio menu, I see OFF/Track 1 for Audio track, Audio channels is grayed out.

The following list of options available for Audio device is:

• Discard all samples (playback) or generate zero samples (capture)
• HDA ULI M5461, ALC 880 Analog Default Audio Device
• HDA ULI M5461, ALC 880 Analog Front speakers
• HDA ULI M5461, ALC 880 Analog 4.0 Surround output to Front and Rear speakers
• HDA ULI M5461, ALC 880 Analog 4.1 Surround output to Front, Rear and Subwoofer speakers
• HDA ULI M5461, ALC 880 Analog 5.0 Surround output to Front, Center and Rear speakers
• HDA ULI M5461, ALC 880 Analog 5.1 Surround output to Front, Center, Rear and Subwoofer speakers
• HDA ULI M5461, ALC 880 Analog 7.1 Surround output to Front, Center, Side, Rear and Subwoofer speakers
• HDA ULI M5461, ALC 880 Digital IEC958 (S/PDIF) Digital Audio Output

The first is used by default and switching between them makes no difference except that HDA ULI M5461, ALC 880 Analog Default Audio Device results in unbearable noise and HDA ULI M5461, ALC 880 Digital IEC958 (S/PDIF) Digital Audio Output mutes all sound.

By searching the forum I found someone's advise to configure vlc to downmix, but I see no option saying downmix in the settings. Am I missing something? What else could/should I look at?

Yes, Ac3 volume is too low.

So, there is no remedy, or is there?

Downmixing is automatic. Just select the correct output w.r.t. to the physical configuration of your speakers. Neither VLC nor ALSA can guess this unfortunately.

hey there..
i'm having exactly the same problem, which i didn't have a couple of weeks ago, but not only with .avi, and not all .avi is messed up: i'm having also with DvD discs, some mkv, and some .iso movie files. I could watch and listen to a specific movie without any issues, but now some of them present this behaviour: low speech but normal music/effects/ambience sounds..

i tried many things, including messing with pulse and alsa (which i don't recommend unless you're pretty confident as what you're doing), but didnt solve it.

What i did notice was: on Pavucontrol (Pulse Audio Volume Control), whenever i open a file and it's sound is alright, i see 2 stream channels for vlc (which should be correct for my setup of just 2 speakers). Now, whenever i open a file that has its sounds messed up (although same file played flawlessly couple of weeks ago), i see at least 4 stream channels, in some cases even 6 channels (like: front-right, front-left, rear-right, ...).

So i tried to find where to force it to use only 2 channels always... i eventually saw this option on Vlc advanced audio tab, to turn off dolby surround , but that didnt work. I guess this is somehow related to this channels thingy, which i'm not sure are related to vlc update (which for my distro occurred 2 or 3 weeks ago -- using Gentoo with Gnome) or what else. I'm right now downgrading vlc to 1.1.11 to see if this keeps happening. Also trying to find a way to force 2 stream audio channels only. Changing my internal audio profile, to any of them, either keeps on happening or i get no sound/terrible sound. Since i never changed it, it always worked fine and it still configured as always was, i'm guessing this is not it.

my info:
Using pulseaudio 1.0-r2
alsa 1.0.24 as auto fallback
Linux insane 2.6.39.3-zen+ #23 ZEN SMP PREEMPT Thu Oct 13 13:48:16 BRT 2011 x86_64
media-video/vlc-1.1.12 (compiled use flags: X a52 aac alsa cdda dbus dts dvd elibc_glibc fbcon ffmpeg flac gcrypt gnome gnutls libnotify mmx mp3 mpeg mtp ncurses ogg opengl png pulseaudio qt4 samba sdl sqlite sse svg truetype udev vorbis x264 xcb xml xv) Vlc updated 10/13/2011 to this version

just a heads up: i can confirm its Vlc 1.1.12 (for gentoo) problem

I played a movie .avi file using Totem Movie Player, and the audio was perfect.
Downgraded vlc to 1.1.11 (from gentoo's portage tree -- no overlay) and yet same avi movie played perfect.

ima stick to 1.1.11 for now until its fixed or a new version comes up

hope this helps

VLC 1.1.12 has problems with more than 2 channels using PulseAudio. The fix has already been pushed a while ago, but some distributions did not pick it up. At least Debian and Ubuntu did pick it up though. If the problem persists, please make sure that your PulseAudio ports configuration is correct: you'll want to use the analog stereo port only, if you only have two speakers. Otherwise PulseAudio will not downmix correctly.

There has not been any change to ALSA between VLC 1.1.11 and 1.1.12. If you have problem there, make sure that you did select Stereo as audio device in the VLC menus. That being said, there were major changes in VLC 1.2.0 w.r.t. ALSA, so testing is much needed.

VLC 1.1.12 has problems with more than 2 channels using PulseAudio. The fix has already been pushed a while ago, but some distributions did not pick it up. At least Debian and Ubuntu did pick it up though. If the problem persists, please make sure that your PulseAudio ports configuration is correct: you'll want to use the analog stereo port only, if you only have two speakers. Otherwise PulseAudio will not downmix correctly.

There has not been any change to ALSA between VLC 1.1.11 and 1.1.12. If you have problem there, make sure that you did select Stereo as audio device in the VLC menus. That being said, there were major changes in VLC 1.2.0 w.r.t. ALSA, so testing is much needed.

Hey, Remi! I know I'm on here a tad late, but I wanted to thank you for the further instructions. I'm working off of Ubuntu, so it's especially strange that I would be experiencing volume/audio issues. Wonder if this'll effect my earphones. I'll definitely attempt to fix the PulseAudio ports config and hopefully that will do the trick. If it doesn't, I'll be sure to come back and see what else I can do. Maybe someone can message me via Skype or AIM to help me out. Anyway, thanks for everything. Peace!

I have the same problem with VLC 1.1.12, on almost every audio output module.
If I use the output module Simple DirectMedia Layer the sound is good.

A follow-up: the problem seems to be gone in vlc 2.0. Thus, update!