Audio sync problems when screen set to 24 Hz (1 Viewer)

[jet70]

Can anyone confirm if they experience 24hz audio lag with mkvs and avi files using Nvidia graphics cards.

I have attempted to scan through this thread and it seems most are using ATI (I certainly am).

If Nvidia avoids this problem, I'll go out and buy a card!

Thanks.

 

[frankwaan]

Can anyone confirm if they experience 24hz audio lag with mkvs and avi files using Nvidia graphics cards.

I have attempted to scan through this thread and it seems most are using ATI (I certainly am).

If Nvidia avoids this problem, I'll go out and buy a card!

Thanks.

Dear Jet70,

I've got simulair problems with a Nvidia 9400GT chipset (on 24Hz). However, it seems to occur mostly when I fastforward to a certain point in a movie (Pulp Fuction for example). When I pause en resume a couple of times, it 'sometimes' syncs correctly. I just can't pinpoint exactly where and when it occurs. I'm not into the Mediaportal SVN very well, but I can imagine it's a hard one to find out (and fix), due to the complexity of the software. I hope it'll be fixed soon though, because I think it's a real showstopper for a lot of people who are slowly migrating to blueray content (23.976fps).

Greets, Frank

Greets, Frank

 

[Rayures]

ok, did some testing today.
First i reverted to cat 9.1 because i read on a dutch forum that cat 9.3 and up have and issue with blanking the screen with 24hz. So far cat 9.1 solves that issue for me. I can now change the refresh rate between 24hz and 50hz without losing the image on my tv set.
Second I installed 1.1Alpha with 04-07-2009 svn update (4-July that is). And the SAF beta18 pack.

When i play a movie (1080p or 720p) is do not have a sync issue. I was very pleased!

But...

I do have a vsync issue on 24hz (also on 50hz but barely noticeable).
I tried all vsync setting in CCC (from always off to always on and all in between). With this tried, i came to the conclusion that MP does set vsync to ON by itself. Because i have massive tearing with vsync set to 'allways off', and only a 'rolling sync band' with all other options. So MP invokes vsync. (i hope i am correct on this one)
Then i tried to use MPC-HC (24hz & 50hz). I disabled all internal filters to that MPC uses the one installed on my system (SAF beta 18 ones that is). There was no vsync issue at all. So i manualy disabled vsync in mpc-hc (keyboard V) and tried again, massive tearing.

So i think that there is something with the MP vsync implementation.

So, on topic of this thread: i have no sync issue with MP1.1A & SVN4-7&SAFb18.

 

[tourettes]

So i think that there is something with the MP vsync implementation.

MP uses vsync on always.

presentParams.PresentationInterval = PresentInterval.Default;

Takes care of it, i.e. DirectX is responsible for the vsync matching. (Requires either EVR + AERO on Vista or Exclusive DirectX mode on XP).

One possibility for the audio drifting could be 23.xxx and 24Hz. Maybe drivers arent handling such small difference correctly? i.e. running video on 24Hz when it actually is 23.xxx could cause the display drivers to lock every video frame to display refresh rate, but the audio would drift slowly)

Just a quess, as I still cannot test this issue on my own HW.

 

[mhunter]

Can anyone confirm if they experience 24hz audio lag with mkvs and avi files using Nvidia graphics cards.

I have attempted to scan through this thread and it seems most are using ATI (I certainly am).

If Nvidia avoids this problem, I'll go out and buy a card!

Thanks.

I have a M3N78-EM which has an Nvidia 8300 on board, I am using AC3 Filter + MPC-HC codec for H.264 via HDMI to my TV Set. When I do this at 60hz, no issues plays back as expected - however when I do it at 24hz, picture is beautiful & smooth but audio gets gradually out of sync. I have to watch for about 5 minutes before I notice this sync issue, and then after about 10 to 15 minutes it's way out of sync. I have experienced this with 700mb divx stereo rips and 1080p MKV's (but that's not to say it won't happen with 720p MKV's). I have not yet tried it with MPC player @ 24hz, but I suspect it will work as the 8300 chipset has been reported to work really well @ 24hz - will try this out and report back when I have time over the weekend.

 

[tourettes]

Everyone who has the audio sync issue, please try following:

1) check if the problematic file is 24fps or 23.976fps
2) make sure that the display refresh rate is exactly the same as found in step 1 (use powerstrip or reclock for example)
3) play file with 1:1 matching refresh rate
4) report back

 

[CypherMK]

Every file I have tried has this problem. The problem occurs with every codec I used. I am now using an external player. That fixes the problem for me. I'm using zoomplayer. Also tried MPC-HC, but that gave me sync issues, when I seek or pause the movie. KMplayer didn't give problems and WMP also didn't give problems. So this is really a Mediaportal problem. But a hard one 2 fix.

Keep up the good work!

Hardware:

MSI p7ngm- digital ( Nvidia 9300)
E5200 Intel
Asus xonar HDAV 1.3

P.s. Tourettes, where r u from? You can debug at my place!

 

[Rayures]

Updated Vista sp1 to sp2 today. For some reason this fixed my vsync issue.

So, I tested some movies this morning with a small hangover from last night and i can not detect a audio sync problem. It looks like i am finally free of all the problems i had. I finally can watch my movies stutter & judder free, with perfect 24hz sync! Just as MP intended

for me the cat9.1, 1.1alpha and 4-7svn did the trick(didn't test 1.1alpha without 4-7svn).

 

[thepahakurki]

I also suffered from audio gradually getting out of sync as well with 23,976fps MKV-files (with 720p or 1080p video) that have ac3 or dts sound tracks.

I was using ac3filter at the time and the sound would always get out of sync after a few minutes of watching. Then I switched ac3filter to spdifer as GhoSe mentions his setup here: 0002060: Audio and video aren't always in synch when refresh rate is set to 24 hz. - MediaPortal Bugtracker

(My setup is WinXP SP3, Geforce 8400gs, CoreAVC with CUDA on, WMR9 and now spdifer)

and the problem is fixed! Sound is in sync now with everything I've tested with: x264 with ac3 or dts, xvid with mp3 sound, mpeg video (recorded tv) etc
I haven't noticed any problems - at least after a few movies, I will test more and report if the problem occurs.

So in conclusion I'd recommend everyone to test if spdifer fixes their problem! (Spdifer | AC3Filter)

 

[rak]

thepahakurki: didn't you changed also the H.264 decoder? As on my setup the out of sync only happens with MPC-HC codec running in SW mode - e.g for x264 incompatible with DXVA. When I changed the decoder to CoreAVC, the audio was in sync again. So I assume it is related to MPC-HC rather than to audio decoder/render. I can't imagine, that spdifer makes any difference over the ac3filer, as I assume that spdifer is only subset of ac3filter functionality made by the same developers.

But to confirm my theory, I'll give a try to the spdifer.