Timeline audio sync

[Anonymous]

Hey All,

When playing audio in a timeline (1080p 23.98) the audio drifts off sync and when I stop and restart playing it is in sync again. Any suggestions?

Thanks,
Zack

[paul.andrews]

Hello Zack,

When you are playing your clip in the large player, do you notice that the small yellow marker that represents the position actually separates into two markers moving at different rates? This would be typical in the condition you describe when picture and audio drift apart. It is a result of a performance issue. This often is caused by the playback performance of the disk array. It cannot keep up with the bandwidth requested to play the clip in real-time.

In preferences, go to the Player tab. Look under the playback column and see if allow drops is turned on. It should be by default. If the player encounters a poor performance condition it will drop video frames in order to keep up with the audio and that yellow marker will flicker yellow, green and blue. If this button is off, you will get all the video to slowly playback in a poor performance condition but at the expense of sync. That is why the two markers drift apart during playback with the green one (audio) seemingly moving faster than the others.

Paul

[Anonymous]

Hey Paul,

I checked into things and there is not a performance problem. This is actually an issue in a 24p and 59.94 project and has got to have something to do with the config files. From what I am told it will not be a problem in a 24psf timeline, but I have not checked into it yet.

Thanks!

[Anonymous]

I'm having video/audio sync issues also. The video plays faster than the audio. In the player the yellow bar is playing way faster than the green audio bar.
No matter what type of footage it's all out of sync. Even SD footage plays out of sync. The funny thing is when I turn off the drop frames in the player prefs the video plays back at 3 times the speed. Running a Mac pro 3,1 with 16gb ram, quadro 4800 and atto FC card and fast ciprico storage.

[Anonymous]

Zack,

Did you ever get this problem sorted out ?? I'm having the same problem right now. Conforming an XML ( 1080i @ 29.97 ) and audio drifts out of sync and when i stop and playback it's in sync again.

[Anonymous]

Was wondering how people were doing with this issue, for it has stricken me as well

[robcoulin]

hi,

i would assume a sync problem -
is the drift relatively "small" (23.97 vs 24) or a lot?
is the timeline in a different format than the project?
are the broadcast prefs matching the timelines frequency?

on linux i would definitely say, that proper audio sync is missing - on the mac im not 100% sure.

robert

[Anonymous]

This is certainly a sync problem. Nothing to do with Computer performance at all.

At least, I have always had drifting audio unless there is an external sync generator connected up to the Smoke. It does the same on Linux or Apple hardware.

You'll need to buy a sync generator (and have it set to the format you're working in) for it to work properly.

You'll need a Tri-Level one if you do any HD work too.

[Anonymous]

same issue here,

i try the dropframe idea.

But sometimes when i deal with strange things in smoke
I get the feeling that smoke is like:
dailydirt.files.wordpress.com/2011/05/dealwithit1.gif

[Anonymous]

Choosing the correct sync for a project

Summary
A Sync Pulse Generator (SPG) produces synchronization signals with a high level of stability and accuracy.
These devices are used to provide a ‘master’ timing source for video facilities.
Autodesk systems require a valid sync connection in order to function correctly.

Why do Autodesk Applications Require Sync?
Sync ensures frame accuracy between the various video devices.
Sync ensures video / audio remains synchronized.
Sync ensures we get the desired results on the preview device.
Required Types of Sync Sources
Use one of the following types of sync for your project:
Bi-Level for Standard Definition Projects.
Tri-Level for High Definition Projects.


Heres the Autodesk Link:
http://usa.autodesk.com/adsk/servlet/ps/dl/item?linkID=9242618&id=15490815&siteID=123112