The VideoLAN Forums

Im getting very choppy stuttering DTS/DD audio over SPDIF using the latest stable build.
Also I noticed that the volume which was previously at a normal level flashes between mute and low volume on the player during this.
Im using onboard Realtek HD audio (S/PDIF optical output to my receiver). Updated to the latest drivers did not improve the problem.
I tried all of the output modules including win32 waveout
I tried using a nightly build of .9 beta which did not solve the problem either.
Overall it sounds very similar to this problem
viewtopic.php?f=14&t=32383
and this one
viewtopic.php?f=14&t=46774

One of the responders to first thread said that
"Simply because there are to few people having issues with it."
If this is in fact a conflict with Realtek HD, this is a pretty significant problem with so many motherboards utilizing this for onboard audio.

VLC is a fantastic player so I would love to be able to continue using it, and Im willing to help out in any way I can. If there is a more formal way of reporting bugs, and if the developers need help isolating the problem or testing solutions, id be happy to help.

Problem isn't only with Realtek HD and it is a serious issue. Did you try Waveout output when you tried with nightly build?

thanks for the reply.

Yes I did try waveout with the .9 beta build.

Hi,

do you have any other applications running in the background - while playing dvd or avi with AC3 / DTS Sound?
- What for OS are you running?
- CPU? CPU-Load?
- RAM?

I can confirm stuttering in the following situations:
- have a running Trillian ICQ Client (I don't know what they are doing)
- an open VNC-Viewer

and I'am running on a AMD 64bit 4800 X2 ... I'am really sure its not the waveout (for me) that sound is stuttering in this situation - the problem must be somewhere else before the WaveOut device.

André
--
atmo

I had a problem with choppy audio/stuttering (some kind of rapid replay of buffered sound, I suppose). It went away after I tweaked the configuration. I'll diff my configs and post the results.

Symptoms/Old config:
* Windows (Vista, XP Media Center, and 2003)
* S/PDIF
* Choppy/stuttering audio with 5.1 (haven't tried DTS)
* Perfect audio with 2 channel S/PDIF
* No video issues (BluRay and DVD video is smooth)
* plenty of horsepower using an E2160 @ 3GHz

After some tuning of VideoLan's config file using the built-in prefs GUI, the 2003 box works perfectly with BluRay and DVDs in 5.1

How I fixed severely stuttering audio in Windows VLC media player

Symptoms:
* Choppy/stuttering audio with DD 5.1 (haven't tried DTS)
* Perfect audio with 2 channel S/PDIF using non 5.1 configs in VLC
* No video issues (BluRay and DVD video is smooth)

Systems descriptions:
* VLC 0.8.6f (I tried other versions, but they also stuttered)
* Windows (Vista, XP Media Center, and 2003 -- 4 different computers running VLC)
* S/PDIF
* plenty of horsepower (E2160 @ 3GHz, fast hard drives, and 2-4 GB RAM, GeForce 7100, 8600 and 8800)
* Various GigaByte motherboards (GA-EP35DS3L, GA-EP35DS3R, GA-73PVM-S2H)
* Realtek audio (ALC889A and ALC888)

After some tuning of VideoLan's config file using the built-in prefs GUI, the Server 2003/GeForce 7100 box started working perfectly with BluRay and DVDs in DD 5.1 S/PDIF. I fixed this about 1 month ago and have heard no stuttering since. One original symptom that I seem to recall was that there was no stuttering on very quiet passages. I think I read about how VLC analyzes audio and then either limits or compresses, and concluded that playing with gain and thresholds might be fruitful.

I'll probably experiment with the other boxes this weekend and document a simple install process clearly identifying the changes from the default VLC configuration needed to have VLC/Windows play 5.1 in S/PDIF. If anyone wants my full working vlcrc file for analysis, send me your email address. But for now, here's some info to help anyone who's in a similar situation, wants to fix their boxes and doesn't need a solution on a silver platter.


Change the "vlcrc" (VLC configuration) file, either using the GUI or an editor. Listed below is a diff of my bad and good vlcrc. I'm not certain which of the parameters fixed it. My surmise is that it's one or more of these three config parameters that made the difference:

the norm-buff-size=10
norm-max-level=200.000000
equalizer-preamp=0.000000



Regards,

Alex Bobotek

----------------------------------------------------------------------------------------------------------------------

Comparing files Bad_vlcrc and GOOD_VLCRC
***** Bad_vlcrc
# High quality audio resampling (boolean)
#hq-resampling=1
***** GOOD_VLCRC
# High quality audio resampling (boolean)
hq-resampling=0
*****

***** Bad_vlcrc
# Hide interface (key)
key-intf-hide=Unset
# Take video snapshot (key)
***** GOOD_VLCRC
# Hide interface (key)
#key-intf-hide=
# Take video snapshot (key)
*****

***** Bad_vlcrc
# Caching value in ms (integer)
#file-caching=300
***** GOOD_VLCRC
# Caching value in ms (integer)
file-caching=1024
*****

***** Bad_vlcrc
# Use float32 output (boolean)
directx-audio-float32=1

***** GOOD_VLCRC
# Use float32 output (boolean)
#directx-audio-float32=0

*****

***** Bad_vlcrc
# DTS dynamic range compression (boolean)
dts-dynrng=0

***** GOOD_VLCRC
# DTS dynamic range compression (boolean)
#dts-dynrng=1

*****

***** Bad_vlcrc
# Global gain (float)
equalizer-preamp=9.800000

***** GOOD_VLCRC
# Global gain (float)
equalizer-preamp=0.000000

*****

***** Bad_vlcrc
# Number of audio buffers (integer)
#norm-buff-size=20
# Max level (float)
norm-max-level=20.000000

***** GOOD_VLCRC
# Number of audio buffers (integer)
norm-buff-size=10
# Max level (float)
norm-max-level=200.000000

*****

some good info here.

atmo , Im using Vista Ultimate 64 bit, no applications running in the background (its my HTPC)
E2200 @ 3.2ghz with 2GB ram and low CPU utilization while playing these files, around 15% IIRC

abotek, I wonder if it is possible to disable VLC's analyzing of audio entirely? The audiophile in me doesnt like the idea of VLC modifying the audio signal to begin with, so if there is a configuration to have VLC just pass through the audio that would kill 2 birds with one stone

Dear all,

Identical problem here, read all forum threads (in/outside this forum)about this subject and tried all offered potential solutions but no results so far :
Hopefully my additional remarks might help this thread in seeking for further / alternative solutions.
When it comes to program debugging I really don't 'talk the talk', I am a user and entirely rely on feedback
from the experts here so forgive my way of below questioning.

config : VISTA Premium, DirectX10, 2.4Ghz, Realtek HD ALC 883 --> S/PDIF 3.5mm to RCA coaxial into 5.1 DD/DTS receiver
notes : VLC is running smoothly, exept A/52 (AC3) audio streams when using SPDIF (DTS identical)
AC3 --> "stereo" over S/PDIF --> receiver PCM is running oke.
WINDVD 9 PLUS and WMP11 give no issue but I consider this different from VLC (themselves Directshow based, VLC not right ?).
In the ALC audio configurator I only activate the SPDIF (deactivate others).

Main solution offered, changing the audio output module to WIN32 waveout extension does not work for me (same results).

1. version 0.8.2. gives however no stuttering.
2. version 0.8.4. (*) and up, incl. last nightly build 0.9.0 gives stuttering (approx. 0.5 sec. sound/silence : receiver display shifts between AC3 and PCM)
question : what can the difference in versions related to this subject tell us ? What has changed which can(not) be altered by users afterwards ?

3. Other threads relate also to "main debug: audio output too slow .." (see VLC menu messages) as is also applicable in my situation.
question : what conclusion can be drawn here and can parameters (which ?) be adjusted to correct this and perhaps result in proper audio over SPDIF ?
question : what is exactly meant by "A/52 over SPDIF". Does A/52 decode or just split A/V before sending over SPDIF or can do both when SPDIF is availabe or just not.

I am not aware if this issue is handled by the developers, who are doing outstanding work anyhow, no questions asked here ! The overall performance of VLC
beats in my opnion the commercial competition, that says enough for me. I experience the audio however just as important as the video to obtain that home
theatre feeling, I guess a lot of people nowadays do. The full use of VLC depends strongly on that for me. Any help will be appreciated enormously !

Best regard,
Martijn

(*) I would like to playback mkv files so I need this version or higher

I just installed a Chaintech AV-710 (VIA Envy24) and Im still getting the stuttering audio, so its not limited to just the Realtek audio.

I have very similar setups to the other posters here and am having the exact same problem....I have also tried all the usual solutions and the problem also occurs in other media players as well...such as media player classic....It is driving me mad.

I have Vista 32bit SP1 - Home Premium

I hope someone finds a solution.

I updated the Realtek Audio Drivers to the latest version and it has appeared to improve the problem....have been watching an AVI file with DD 5.1 streamed from my computer to my Reciever and it appeared to only stutter once at the begining...it has been running for a good 10 minutes...

I also got rid of AC3 filter....just for troubleshooting and am running the movie in Media Player Classic....

VLC does not work...it just comes out as a garbled digital noise

I uninstalled all audio drivers and am using generic windows drivers and the AVI DD Audio seems to work fine....it did cut out briefly but that was 20 minutes into the audio file....

Hi Everyone.
I have a New System Setup and same Stutter and hesitation with any video with 5.1 Audio, but only with VLC. Tried every conceivable suggestion listed in here, and other ideas, and unfortunately can not find a Vista remedy. Tried many VLC versions and the Beta with the New Vista OS and the similar System Hardware and Software posted. I booted into 64 Bit Linux Distro's Opensuse 11 and 3.5 Sabayon and the VLC Players had No problems and exhibited excellent performance. With Windows since Vista, the DRM and it's Recommended updates, then who
knows? But I sincerely really hope VLC developers pay attention enough in here to find a solution for everybody.
The New VLC Beta is fantastic.

This isn't only Vista related issue (happens with all Windows versions). Or nothing to do with DRM.
digitall2: you tried Nightlies with Waveout audio output module (pressed Save and restarted VLC before trying)?

This isn't only Vista related issue (happens with all Windows versions). Or nothing to do with DRM.
digitall2: you tried Nightlies with Waveout audio output module (pressed Save and restarted VLC before trying)?

Yes, I tried the Nightlies, Waveout Audio Output Module and many other modifications too and always use Save (lol) and restart with no joy.
My XP Homes and XP Pro P4 Systems to not have this significant playback problem and from other reports it appeared to be with Vista, then
that was my bad. I have used VLC just wonderfully for many years on many a System and the few, relatively insignficant issues, which I can not
even remember, were easy to adjust. Now an exclusive 64 bit Intel Q6700, Vista 64, Realtek ALC888, nVidia 8600GT and VLC has this Sound
Hesitation that can be reduced for me by trying the many suggestions that are around the Net, but far from completely fixed....even with
different System and Hardware Drivers and Codecs. Guess it is Just the Luck of the Draw on this Windows Machine for this Round

I found this fixed the issue for me:

http://www.instructables.com/id/Fix-aud ... LC-Player/

After doing what that site asks you to do, close down and restart VLC.

However I experienced the audio breaking up, so I tried 0.9.0 test2 and the audio now sounds normal.

I found this fixed the issue for me:

http://www.instructables.com/id/Fix-aud ... LC-Player/

After doing what that site asks you to do, close down and restart VLC.

However I experienced the audio breaking up, so I tried 0.9.0 test2 and the audio now sounds normal.

Hello gaziggi. I tried the Nightlie, and low and behold, I am in a of state of happiness euphoria, as now the Audio Stutter is finally gone.
The 5.1 with VLC is more beautifully pronounced than any other Player I've tried in Vista.
Did have to set Audio Output Type to "Win32 waveout extension output" to get it right.
Thanks to the Developers and those Nightlies that corrected this issue, so please
"Bring On The Awesome Final"

I found this fixed the issue for me:

http://www.instructables.com/id/Fix-aud ... LC-Player/

After doing what that site asks you to do, close down and restart VLC.

However I experienced the audio breaking up, so I tried 0.9.0 test2 and the audio now sounds normal.

Hello gaziggi. I tried the Nightlie, and low and behold, I am in a of state of happiness euphoria, as now the Audio Stutter is finally gone.
The 5.1 with VLC is more beautifully pronounced than any other Player I've tried in Vista.
Did have to set Audio Output Type to "Win32 waveout extension output" to get it right.
Thanks to the Developers and those Nightlies that corrected this issue, so please
"Bring On The Awesome Final"

Final should arrive soon.

Can you answer two questions:
- Was the suttering fixed in normal audio output mode ? Yes/NO ?
- Was the suttering correctly fixed after used of Win32 Waveout? Yes/No ?
- What is your Vista version ?

Can you answer two questions:
- Was the suttering fixed in normal audio output mode ? Yes/NO ?
- Was the suttering correctly fixed after used of Win32 Waveout? Yes/No ?
- What is your Vista version ?

- If by normal audio output you mean audio without setting it to SPDIF out, then yes there was no stuttering. However that won't give me surround sound.
- The stuttering was fixed after I set it to Win32 Waveout. In version 0.8.6, the audio was breaking up.
- Vista version I have is Vista Home Premium with service pack 1.

Try this build: http://nightlies.videolan.org/build/win ... 0814-0146/

Be sure to set Output Type to: "Win32 waveOut extension output"

It will solve all your problems with SPDIF...

/Andreas

I found this fixed the issue for me:

http://www.instructables.com/id/Fix-aud ... LC-Player/

After doing what that site asks you to do, close down and restart VLC.

However I experienced the audio breaking up, so I tried 0.9.0 test2 and the audio now sounds normal.

Hello gaziggi. I tried the Nightlie, and low and behold, I am in a of state of happiness euphoria, as now the Audio Stutter is finally gone.
The 5.1 with VLC is more beautifully pronounced than any other Player I've tried in Vista.
Did have to set Audio Output Type to "Win32 waveout extension output" to get it right.
Thanks to the Developers and those Nightlies that corrected this issue, so please
"Bring On The Awesome Final"

Final should arrive soon.

Can you answer two questions:
- Was the suttering fixed in normal audio output mode ? Yes/NO ?
- Was the suttering correctly fixed after used of Win32 Waveout? Yes/No ?
- What is your Vista version ?

Q #1 Ans. NO (Default)
Q #2 Ans. YES (Win32 WaveOut)
Vista 64 bit Home Premium SP1

Tried the above Nightly suggestion post by acana79 and set Audio as he suggested to fix
very scrabbled Sounds with SPDIF, as stuttering could be not be actually heard with all the
Harmonic distortions. Audio plays fine with set to Win32 WavOut.

Great. So SPDIF is fixed complety in WaveOut... This seems great...

Just tested on the newest version last night (.9.8a) and it is still broken.

what is the status of this bug?

Works for me.