1 Topic by razelik (edited by razelik 28-03-2015 09:48:55)

Topic: Audio out of sync

Hello guys, i'm new here so lets begin... I use SVP first time on windows 8.1 64bit with ( Intel i5-4460 3.4 GHZ with a GTX 660 OC and 8 GB ram ) and all was fine, 2 days ago i reinstall a fresh clean copy of windows 7 64bit, all was ok, i installed SVP and i saw that my audio is out of sync but not always sometimes has a delay of +200 sometimes has no delay i think is something random, i use MPC-HC, cpu 40% when i play 1080p i'm mad because on windows 8 all was working fine, so what i can do to solve this problem, thanks

http://i59.tinypic.com/2yttrtg.jpg DPC Latency Checker

  • MAG79
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Re: Audio out of sync

razelik
It is great if you can hear +/-200 ms audio shift smile I can hear only +/-500.

I think you can help us to find the place where audio shift is created.
First of all I need to ask you some questions:
1. Do you use ReClock? What color of icon it has (must be green)?
2. What renderer are you using? What it say about audio delay in its statistics (Ctrl-J)?

As you can see you can eliminate this audio desync:
1. by enabling/disabling ReClock.
2. by changing Renderer in MPC-HC (menu View - Options... - Playback\Output page - DirectShow Video).

It is not all but we can start from these two steps wink

  • Thanks: 4

Re: Audio out of sync

Nobody must read my posts about audio going out of sync. For me it never ever has anything to do with reclock or renderers, but always avisynth / ffdshow setup. Try changing ffdshow buffer ahead settings. See here http://www.svp-team.com/forum/viewtopic.php?id=1835

Nobody seems to know whether its going to be possible to fix these issues as ffdshow is pretty much end of life at this point. MAG79 any idea if these can be fixed by somehow running avisynth without ffdshow?

  • MAG79
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Re: Audio out of sync

mark007
somehow running avisynth without ffdshow?
You can Generate AVS script by SVP menu - for video encoder. Then Close SVP. And then open this AVS file in your player. wink

Re: Audio out of sync

Sorry for late post,  i found the problem big_smile i have 3 monitors connected to pc ( 2 of them on cpu gpu, 1 on dedicated gpu) when i open any video on the dedicated gpu monitor, MPC-HC stats (ctrl + j) show that i use gtx 660 as render device, when i start video (Play video normal) on other 2 monitors connected to cpu gpu, the stats show i use integrated gpu hd 4600, so the problem was when i used dedicated gpu and move MPC-HC on integrated monitor and same integradet gpu to dedicated gpu i get that lag and sound delay
PS. I see that only in fullscreen if i use Nvidia Cuvid as hardware acceleration all is smooth, when i use DXVA2(copy-back) i get lag.

http://i59.tinypic.com/1213kmx.jpg
http://i60.tinypic.com/ayubzl.jpg

Re: Audio out of sync

@Mark, i see that you can get audio and video out of sync by editing video profiles, try to low the settings  http://i59.tinypic.com/35kq2s8.jpg, if to other of us work ok, then the problem i think is hardware(lowspec) or that usb capture you use in my op... big_smile

  • Thanks: 4

Re: Audio out of sync

MAG79 wrote:

mark007
somehow running avisynth without ffdshow?
You can Generate AVS script by SVP menu - for video encoder. Then Close SVP. And then open this AVS file in your player. wink

Oh wow. But how can I use avisynth while playing a DVD or bluray through mpc for example. How can say lab decoder feed into avisynth?

Razelik. No I have changed hardware over the years amd thr issue remains.

Currently GTX 980 with core i7 @ 3.6ghz. There's definitely issues with ffdshow interacting with avisynth when it comes to thread counts and buffer ahead sizes so in hope to elimate ffdshow from filter chain but not sure how to still use it without ffdshow without comprises

I have given up on hope of a fix.

Re: Audio out of sync

so the problem is only on your machine ?

9 Reply by mark007 (edited by mark007 31-03-2015 20:21:28)

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Re: Audio out of sync

No. On doom9 forums as well as this thread itself wink and many more threads in this forum reporting audio out of sync where resources arnt the issue.

How could very specific ffdshow buffer ahead cause audio desync when one value above or below doesn't... if its not some issue between ffdshow and avisynth...

I welcome you to also play with ffdshow buffer values to reproduce. I found 15 to be perfectly in sync for my current setup so I leave it as is but still the question remains why does it cause audio desync if its not tuned like I did. GPU usage on my system is extremely low. The fans don't even spin. CPU usage is around 40%

Re: Audio out of sync

could nvidia driver settings do this? you try to use vsync off on your nvidia control panel ? idk just say... because your cpu/gpuits on low usage http://i60.tinypic.com/2agok6g.jpg so its not hardware, i dont think its only avysinth and ffdshow because im still thinking if that was a (ffdshow/avysinth) problem, we all use to have this  kind of bug...

  • Thanks: 4

Re: Audio out of sync

But do you use SVP manager or custom script that uses SVP DLLs. I use custom script and find varying ffdshow buffers show different audio sync results across all of machines

I guess SVP manager sets one fixed buffer ahead value?

I have vsync forced on. No setting should ever cause audio to go out of sync but for me ffdshow settings are all that ever effect it so there's definitely an issue with it.

If you are still having the issue I'd suggest to try custom script and play with buffer ahead values. At least that was a good workaround for me and shows the root cause of the issues at least for my machines is ffdshow buffer ahead values.