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Hi!

I also had problems with stuttering sound while using "A52 over SPDIF". Not anymore!

To sum up, both these workarounds succeeded... Kudos to them who came up with the solutions!

The "clean one":
Settings-->Preferences-->Audio-->Output modules
Check the "Advanced options"-checkbox
Switch from "DirectX output" to "Win32 waveOut extension output" in the drop-down-box.
Save the settings and restart VLC.
Voilà!

The "dirty one":
Install VLC version 8.2 in a temporary folder.
Copy "libaout_directx_plugin.dll" in the "plugin"-folder.
Switch to the corresponding folder of VCL version 8.6a.
Make a backup of this "libaout_directx_plugin.dll".
Paste.
Save the settings and restart VLC.
Voilà!

I'm gonna give this a shot. I just bought a new sound card and wanted to use SPDIF and VLC, but the thing was stuttering like crazy with the digital audio hooked up to my home receiver.

The clean one worked!

Hi, again...

I just set up a new user account on my computer and was faced with the same spdif problem once again. I realized that you have to restart VLC for the settings to be activated in the "clean one" solution.

Btw... dunno if the solutions applies to other versions than 0.8.6a.

Another thing I’ve encountered is that if you set the audio output module to “Win32 waveOut extension output” and you still get the choppiness, try this: while the DVD is playing, disable the audio track and re-enable it again, this seems to have solved the issue for me.

Now if only there was a way to make VLC switch between “Win32 waveOut extension output” and “DirectX audio output” when S/PDIF single is detected (like Media player classic), then I wouldn’t have to constantly go into the preferences to change these outputs.

Anyway, just thought it might be useful for anyone that’s still having this problem.

Can anybody explain why the following happens with the "clean" method.

Once I select “Win32 waveOut extension output” the 5.1 sounds work throught S/PDIF but after that sound levels overboard drop to about half. Now this happens with every sound I output from my system be it through S/PDIF or analogue. Rebooting does not solve the issue and the only way to get my sound levels back is to reinstall my AC97 drivers

Any guesses what could be causing this?

System:
XP SP2
Asus A8N-E
Latest AC97 3.99 drivers

I love you!!!!

Thank you, this has been bugging me for ages and finally I can use spdif

Cheers

Can anybody explain why the following happens with the "clean" method.

Once I select “Win32 waveOut extension output” the 5.1 sounds work throught S/PDIF but after that sound levels overboard drop to about half. Now this happens with every sound I output from my system be it through S/PDIF or analogue. Rebooting does not solve the issue and the only way to get my sound levels back is to reinstall my AC97 drivers

Any guesses what could be causing this?

System:
XP SP2
Asus A8N-E
Latest AC97 3.99 drivers

If you join channels the electrical and acoustic build up is 6 dB (twice the volume). Also if you have a mono signal in the left channel only and you add the right channel the build up is again 6 dB because you are adding another stage of the same gain. When you split the sum of the respective stereo channels the gain should maintain because of the added stages. Unfortunately there are a number of things that get in the way of the math.

1. Headroom and average levels change in a sum by 6 dB if not compensated for by reducing the gain by the amount of the sum (-6 dB) only for the forms that use the sum (5.1 to 2 channels). Thus Gain and Headroom is calculated in the stereo form and the 5.1 sum to 2 channels maintains the Gain and Headroom.

2. Dolby's ac3 has an average level (by specification) that is 8 dB below most other formats. However, DTS has normal gain compared to other formats. Also speaker positioning and environment has allot to do with how we perceive level in a 5.1 format. Example: If the speakers are placed in each of the four corners of a room the front speakers will always appear louder than the rear by about 3 dB. Thus the reason that the rear speakers are placed more to the side rear and yet at equal distance from the listener. Assuming that the speakers are all at the same level both electrically and acoustically the split should actually be louder than the sum by exactly 6 dB or twice the volume while still maintaining the gain and headroom of each converter sent to each of the respective amplifier and speaker.

3. In surround sound mixing (the person finalizing the sounds) how this works in Movies varies greatly over the creative mixing of CDs or DVDs used for Music. In Movies the center channel traditionally had dialog and the stereo channels had sound effects and Music. Today in 5.1 the dialog has expanded (in many cases not all) into the stereo and the sound effects into the surround speakers. Music for the movie is most always in front of you with ambiance or air of the orchestra to the rear speakers. What this all means is the rear speakers rarely show the same levels as the front speakers Typically (again) by 3 dB so there is no good way to compensate for movies. Now for Music where the mixing is meant to envelope the listener and place them in the middle of the event the sounds out of the speakers are considerably more equal and the split should be 6 dB louder than the sum.

4. VLC like many other computer programs are aware of the change in gain and have compensated incorrectly for the sum and split into the respective channels. I have tried writing about this before and have never received an answer. AC3 (5.1) in a program like VLC is not going to be 8 dB lower in sound. It will be 14 dB lower in sound or still 6 dB lower than its stereo counterpart.

5. Now we enter another element of 5.1 sound called DRC (Dynamic Range Controller) which is a fancy name for a limiter or compressor where low sounds are perceived louder and high level sounds are made softer. In most cases the use of such devices will make the over all sound softer and some devices offer a gain make up of which VLC does not and the DRC is on by default for both ac3 and DTS in VLC. Try shutting off the DRC and listen again. The sound will be more natural and clearer and a bit louder by approximately 1.5 to 3 dB depending on the source.

I tried both fixes. I followed the instructions completely, but neither worked for me. The clean fix results in no audio. The dirty fix also results in no audio and removes the DirectX audio output module from my audio output module choices. I guess it's back to version 0.8.2 for me unless someone has further suggestions.

5. Now we enter another element of 5.1 sound called DRC (Dynamic Range Controller) which is a fancy name for a limiter or compressor where low sounds are perceived louder and high level sounds are made softer. In most cases the use of such devices will make the over all sound softer and some devices offer a gain make up of which VLC does not and the DRC is on by default for both ac3 and DTS in VLC. Try shutting off the DRC and listen again. The sound will be more natural and clearer and a bit louder by approximately 1.5 to 3 dB depending on the source.

Hey there DJ, sorry it took so long to reply, I started to mess with this issue again when VLC 0.8.6b was released. Here are my findings so far:

When Audio output module "default" is selected, boosting the volume level over 100% works fine with 5.1 and 2.0 video files and also the volume level is fine. Now to get 5.1 truly working with S/PDIF I must select Audio output module "win32 waveout extension output". After this 5.1 video files (with audio device a/52 selected) volume level is the same when trying to change volume level in VLC, I have read that with S/PDIF truely enable you can only change volume with amp? So everything seems to be OK with 5.1 material.

But when "win32 waveout extension output" is selected and Iam watching 2.0 material, the sound levels are way below what Iam getting with "default" audio output module so I have to crank my amp volume really high to get some volume out. Also going over 100% volume level does not seem to be working when "win32 waveout extension output" enabled, because volume level 100% is as loud as 200%. With "default" audio output module the volume levels are generally much higher than with "win32" and also boosting volume over 100% works.

Anyways I can live with changing the Audio output module from "default" to "win32 waveoutput method" depending on whether Iam watching 2.0 or 5.1 videos. Just wondered if this is how its supposed to work

Also found what seems to be a bug. VLC crashes everytime when I enable settings/extended GUI/equalizer/and tic then enable (preamp) button. This happens with 5.1 video using "win32 waveout extension output" and while a/52 audio device is selected.

ps. I reread DJ your posting and I must say, thanks for the very informative post. I have always wondered why 5.1 Dolby material sounded so much quieter than other formats

You post is a little scattered for me even though I read it a couple of times.

1. The volume control will not work in S/PDIF mode

2. In my opinion VLC is NOT correct in their sum and split values causing problems of improper gain between 2 channels and 5.1 channels or the other way around. But I don't believe this effects S/PDIF.

3. Your crashing when the EQ is inserted is not normal. I would try a different set of audio drivers or audio card.

4. Your not perceiving the difference between DRC on or off, you must press Save and close the player for the changes to take effect. But it may be a resolution issue for the audio card or and environment issue for the way the speakers are set up or the acoustics of the room null the change. This is an obvious change for me and has been in every program that offers DRC.

5. The books say that 3 dB in level is the minimum perceivable change for level or frequency. When in fact (good equipment and environment) we can perceive 2/10 of a dB change in level and frequency.

My english is lacking and I know it must be hard to comprehend it, thanks for trying still!

I solved my main issue however! The issue where I complained about the lower volume levels with "win32 waveout extension output". Well it turns out to be my own fault or something has changed during VLC versions. I have this habit of setting the Defaul Audio Volume to low 32 since some of my videos have very loud audio tracks. Now get this:

When I set the Audio default volume level to say 256 and start cranking up the volume in VLC, I get very loud sound just fine. If I set the default volume level 32 and crank up the volume from there, the sound level even at max is still very silent. I know this must sound crazy but there is a huge different. Quess the VLC works under different logic than my brain, since to me no matter what the default volume level is at the beginning, it should get equally loud when you max the volume in VLC ?? Very confusing to me.

So basicly now my VLC is working fine for me. I get deacent volume levels with my stereo video files (default audio level at 256) and my 5.1 videos also work. Still enabling preamp with 5.1 video files crashes VLC, but its not a big problem for me as I can always crank up the volume from my amp. I really suspect that most of these issues are due to Realtek drivers, but what choice do I have, either its Creative (which drivers are not too shabby either) or integrated sound cards :/

Here is the error when enabling preamp with 5.1 video:

ppName: vlc.exe AppVer: 0.8.6.0 ModName: libvlc.dll
ModVer: 0.0.0.0 Offset: 00049b5c

That probably dont do much good :/

I have a question here, would they make any difference between
"spdif enabled" and "spdif disabled"?

What is SPDIF doing?
I have Creative Sound Blaster Audigy 4 with 7.1 stereo.
But I never used SPDIF before, coz I didn't know much about it.

Could anyone help clarify my mind, please?

My english is lacking and I know it must be hard to comprehend it, thanks for trying still!

I solved my main issue however! The issue where I complained about the lower volume levels with "win32 waveout extension output". Well it turns out to be my own fault or something has changed during VLC versions. I have this habit of setting the Defaul Audio Volume to low 32 since some of my videos have very loud audio tracks. Now get this:

When I set the Audio default volume level to say 256 and start cranking up the volume in VLC, I get very loud sound just fine. If I set the default volume level 32 and crank up the volume from there, the sound level even at max is still very silent. I know this must sound crazy but there is a huge different. Quess the VLC works under different logic than my brain, since to me no matter what the default volume level is at the beginning, it should get equally loud when you max the volume in VLC ?? Very confusing to me.

So basicly now my VLC is working fine for me. I get deacent volume levels with my stereo video files (default audio level at 256) and my 5.1 videos also work. Still enabling preamp with 5.1 video files crashes VLC, but its not a big problem for me as I can always crank up the volume from my amp. I really suspect that most of these issues are due to Realtek drivers, but what choice do I have, either its Creative (which drivers are not too shabby either) or integrated sound cards :/

Here is the error when enabling preamp with 5.1 video:

ppName: vlc.exe AppVer: 0.8.6.0 ModName: libvlc.dll
ModVer: 0.0.0.0 Offset: 00049b5c

That probably dont do much good :/

If you do a search here, there is a resolve for both the Realtek and Audigy.

One of the reasons I registered today was to vote that the Clean Method worked for me and to voice my gratitude that DD/DTS 5.1 is now an option on the VLC player on my MCE 2005 PC. I'd pretty much given up hope until I saw this thread.

One of the reasons I registered today was to vote that the Clean Method worked for me and to voice my gratitude that DD/DTS 5.1 is now an option on the VLC player on my MCE 2005 PC. I'd pretty much given up hope until I saw this thread.

success here to after giving up with this player in the past!

suggest they make this thread sticky for other users

Though it gets a little closer to working than previous attempts... I get a continuous stuttering in and out of sound as opposed to the endless loop of one sample I used to get.

If I look at my receiver it is switching back and forth from 2 channel DD to 5.1 to 7.1 several times a second.

Which doesn't happen on the same track with Media center and the AC3 plugin/filter.

What is your sound card?

SigmaTel onboard from an Intel Badaxe2 Mobo.

I have the same problem as flummox1. With "default" and SPDIF, I hear an endless loop, with "win32 waveout" the sound is clear, but stutters every 2 - 3 seconds. In Powerdvd or Zoomplayer with AC3 filter 5.1 sound works without problems. System: Vista 64 Bit with Soundmax (ADI AD1988) onboard sound.

Any solution?

Look for drivers. Search the forums for your chip set to see if others here have found a solution.

Or just use Media player (gasp!) since it seems to work fine until VLC is fixed in a future version.

I don't believe the DirectX module is scheduled for any changes in the next version (0.9.0). Considering there are no problems with using S/PDIF and the older method of addressing the audio card (Win32 waveOut extension output) it is doubtful anything will be done anytime soon. Also considering the only people having issues seem to refuse to believe that the problem could be the audio card (drivers) on their end, I guess they will continue to blame VLC and not try to fix the issue.

Please.

Agree it could work fine with other audio cards/chipsets but the fact remains it works with other programs and not with VLC. For whatever reason. Maybe the drivers are at fault but other programs make it work and VLC doesn't. Since I'm on the most recent driver simple troubleshooting says to spend time looking at the one thing that isn't working... not things that are.

Okay, DJ...I have been in these forums for what seems like days, and I have noticed that you seem to be in complete denial that there is a problem with VLC and spdif. Just look at the poll on this thread! A GREAT NUMBER of people did not have any luck with either fix.

I just upgraded my Realtek drivers with ones that came out literally last week, so my drivers are up to snuff. Others here have continually stated that other players do fine with spdif.

In every case, your immediate response is "the problem is on your end" when it is pretty obvious that there seems to be a massive flaw in VLC that doesn't handle ac3 through spdif. Why are you in denial of this fact?

And if you can't help these poor frustrated folks (me included) then try this...just don't post a response. I loved the novel you wrote to the guy whose volume was lower, then it turns out that its lower because he forgot to turn it back up.

You are obviously very knowledgable, so dude...help us with this problem...don't deny it exists. You seem to be one of the smartest guys in this metaverse and if you solve this, you will be a freaking HERO, so please....use that big ol brain for something other than saying "its not vlc's fault."

Sorry to be such a jerk, but its been a loooong week. Help us, DJ Kenobi...