audio problem (skipping)

[Freeman]

hi

i noticed that if other programs are working (taking some process time) the audio is stronly skipping because vlc seems to have not enough process time to keep up.
i can easily reproduce this, for example if i'm just scrolling a window,
but even a folder change in windows explorer can trigger audio skipping.
it's very annoying. because i have an 2.8ghz P4, so there should be enough cpu time left for vlc, with other players this never happens.

but if i manually increase the process priority via the task manager, this problem doesn't occur, there's also an option in vlc preferences to increase process priorioty but that one doesn't help.
only if i do it manually with taskmanager. but i have to do it everytime vlc is restarted.

maybe some know of this problem, because even with normal priority this audio skipping due to low process time shouldn't happen with a 2.8ghz

thx folks

[Dandruff]

yes -> same annoying audio-dropouts here (opening internet explorer for example causes them). running pentium 4 (2.5 ghz) here. all other applications don't have this problem.


please fix that in an upcoming version! thanks!



_____________________
windows xp sp1
vlc 0.7.2

[The DJ]

It's more because vlc doesn't do much buffering i think.....
so if it can't access the HD right away, you get a buffer underrun.

[Dandruff]

no other application (winamp, foobar2000, windows media player and so on) have problems here!! they all running fine and 100% skipping-free (also at high cpu-loads) at normal priority! so it is a problem of vlc! really! vlc already has problems at really low cpu-loads (~1%). just open internet explorer and audio drops out. really bad!


DMA for my harddisk (7.200rpm drive) is also enabled here! and my machine has 1024 MB RAM. so where's the problem?????????

[The DJ]

That's because they have huge buffers unlike vlc.

[Dandruff]

i've changed all the buffers from 300ms to 1000ms now, but that doesn't really help at all!?

what's the reason of having small buffers, if a machine (with more than 2ghz) can't really handle them proper (so that you can open some applications without audio-dropouts)???

[The DJ]

It's because small buffers are better for real time streaming. Which was the original purpose of VLC.

[Dandruff]

ok. what about a checkbox (realtime streaming / offline viewing) then? or something similar that prevents the audio-dropouts ...

[The DJ]

It's in the pipeline, but it's a lot of low level work that will take some time to finish.

[Dandruff]

i'm glad to hear that. thank you!

[Flameon]

I also got problems with the sound skipping. Where do I change the buffer-thingy? That was mentioned above.

[Dandruff]

it's called "caching value" at the several access-modules. but it doesn't help. there's no option to change the output-buffer for/to the soundcard.

[Gibalou]

Another option that might help, in preferences -> misc -> "Increase the priority of the process".

Try to enable this one.

[Dandruff]

this doesn't help. has zero effect.

[Halo]

Just popping by to mention I also have this problem.

Seems to just be with audio though, haven't noticed much skipping in video, etc.

Here's some specs in hopes they will help find the issue faster.

Pentium 4 2.4ghz
512mb ddr333
Onboard AC97 sound /w Asus P4PE Motherboard.

[tomleonard]

Isn't it about time this problem was fixed. It's been a critical issue for me for over a years and stops us from deploying VLC on a larger scale. Regardless of whether or not the payer was designed for streaming, the fact remains that a great deal of usage is playback of local files.

Yet again, this issue has been pushed to the next milestone.

[Sync]

Skipping still exist as of the time of this post. Is this bug ever going to be fixed?

[Yawn]

Try do this :

Go to RUN and

digit DXDIAG, then go to sound and enable 3d sound.

Then the skipping should be gone....

[Sync]

Sounds like you are using a very very very old version of directx. When you upgrade to DirectX9 there is no enable 3d sound, only Hardware Sound Acceleration Level -> Full acceleration.

[DJ]

I find it interesting that no one in this thread has mentioned formats. Or if indeed it is all formats no one has updated their audio drivers assuming the problem has to be vlc because another player isn't doing it.

All players use DirectX differently, has any one tried to shut down DirectX and use the older access method? Considering DirectX was mentioned in this thread then "Win32 WaveOut Extension Output" would be the older access method. The answer then become easy. If it works update your audio drivers and turn back on DirectX. If it doesn't work throw away the audio card and buy a new one. All digital video is follow audio for sync when the audio is not accepting control or is not providing control for the video or the video is not accepting control (more rare these days) it's time to get a new audio card. The symptoms are popping in the audio for all formats to not playing at all. Of coarse you are always welcome to update DirectX the runtime is updated every few months (6/06) they are not automatic and the version does not change from 9c.

[Sync]

That is the problem though. Only VLC have this problem. No other video player have this problem. That reduces the scope to VLC and VLC only. Therefore there is nothing wrong with the audio drivers, no the audio card itself, only the program.

[DJ]

I have heard this argument before and as long as you believe it the problem will never be fixed.

Even Microsoft recommended updating your audio and video drivers after SP2 for XP as that's when most people got DirectX 9c. But it never really stopped there. As APIs change and are updated you must also stay current. If you don't want to do this go back and use an older version of VLC. 0.8.2 for example, does not require updates and should run with SP1 and earlier, Windows 2k and 9x - me. Many users are asking why it seems to run better, Yet! I stay current and don't see their problems!

BTW I don't have sound skipping or lip sync or jitter problems either and my dshow system is up to date with VLC so I can always get a second opinion. In fact three out of the last five downloads ran better in VLC than they did in dshow and one of them was a WMV3. The other two ran about the same or equal. But I'm constantly looking for dshow codecs and updating and running comparisons which most people don't or won't do! I have also gathered a set of tools that keep me from having conflicts in dshow and know what stuff to stay away from. Not saying the system is perfect by any means because if I were to reload the system I know I would do it differently.

Now I have talked about Windows allot here, but VLC is a single source code that is compiled on the box and operating it was intended for as such it is highly dependent on that operating system and the hardware installed. When VLC has a problem is shows up in all operating systems. When your system has a problem you are alone or perhaps you can find a few other sympathizers who share your dilemma like this thread. But you will notice no one here has mentioned an operating system or any thing else specific and every one believes the problem is VLC, so I guess you are in the right place.

[The DJ]

fact is, most players use WaveOut, and not DirectX. VLC uses DirectX.

[Dandruff]

fact is, most players use WaveOut

? maybe 10 years ago. most players use wdm (directsound) these days ...

[DJ]

I must agree here. I use GraphEdit allot and Gabest's MPC often looking at filters. I find most players use DirectX. In fact I don't believe I have one on my machine that doesn't or have tried one that doesn't.

Now, if you would like to talk about S/PDIF usage. This is a bit different story.