Solved - Audio out of synch, video jumping

Steve1967

Newbie Private Message Joined: Mar 18, 2023 19:20 Messages: 7 Offline

Solved by

Mar 18, 2023 21:50

I just got a new computer and installed PD365, transferring from an older laptop that was seriously under powered for video editing. On the new machine when I play a video the timeline tracker and audio are out of synch with each other and with the video. For ex, even using the default skateboard clip, the audio runs out a couple seconds before the video ends, and you can see that the timeline tracker is not lining up with peaks and valleys in the audio waveform. The tracker also skips ahead in big steps as it nears the end. These effects are inconsistent, sometimes happening and sometimes not, and sometimes happening differently than in a previous playback. The attached video shows 3 passes. #1 is pretty OK, #2 and #3 are not. A video without sound will skip ahead as well, and seems to happen in the back 1/3 or 1/4 of the video, like it's trying to catch up to where it's supposed to be.

Troubleshooting so far -
1) Restarted both the computer and PD.
2) Tested with other videos and audio clips.
3) Tried reducing the video playback quality, turned off shadow files, and optimized GPU acceleration settings.
4) Tried it with hardward decoding on and off, and with and without rendering the preview.
5) Uninstalled and reinstalled PD.

Thanks for any help!

Filename	20230318204250.mp4	Download
Description	Skateboard clip glitches
Filesize	26103 Kbytes
Downloaded:	30 time(s)

This message was edited 2 times. Last update was at Mar 19. 2023 11:46

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optodata

Senior Contributor Private Message Location: California, USA Joined: Sep 16, 2011 16:04 Messages: 8411 Offline

Mar 18, 2023 23:45

It looks like your system might be busy doing something else. What does Task Manager show for the CPU load when you do this?

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Steve1967

Newbie Private Message Joined: Mar 18, 2023 19:20 Messages: 7 Offline

Mar 18, 2023 23:54

Quote It looks like your system might be busy doing something else. What does Task Manager show for the CPU load when you do this?

Thanks for your reply. It fluctuates between 10%-15%.

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optodata

Senior Contributor Private Message Location: California, USA Joined: Sep 16, 2011 16:04 Messages: 8411 Offline

Mar 19, 2023 00:17

I can't imagine any system skipping like that with an HD clip, nevermind a brand new one. I also don't know what might be happening when a pre-rendered preview can't be played back fluidly.

Just for fun, can you run the DxDiag test and attach the results as shown here?

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JL_JL

Senior Contributor Private Message Location: Arizona, USA Joined: Oct 01, 2006 20:01 Messages: 5802 Offline

Mar 19, 2023 08:58

Quote I also don't know what might be happening when a pre-rendered preview can't be played back fluidly.

In this case, since they just have a clip with no editing mods in the timeline to decode and apply, any form of Render Preview will make the clip larger and more complex to decode and playback.

Basic clip for NTSC timeline, 1920x1080, 4.79Mbps

For Render Preview:
Full HD Preview, 1920x1080, ~20Mbps
HD Preview, 1280x720, ~20Mbps
High Preview, 640x360, ~8Mbps

The timeline decode bitrate requires more computation for Render Preview at any preview quality setting and all are more demanding than decoding the basic clip, so the fact it didn't help is not at all surprising.

Additionally, other than the audio being demuxed which is advantageous, the audio can become more complex and larger depending on user timeline audio setting when using Render Preview.

Jeff

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Steve1967

Newbie Private Message Joined: Mar 18, 2023 19:20 Messages: 7 Offline

Mar 19, 2023 09:08

Quote I can't imagine any system skipping like that with an HD clip, nevermind a brand new one. I also don't know what might be happening when a pre-rendered preview can't be played back fluidly.

Just for fun, can you run the DxDiag test and attach the results as shown here?

Thanks again. Here is the dxdiag file. Also attached is a screen grab of the issue with the task manager running showing the load. This clip was just dropped in the timeline and not pre-rendered.

Filename	DxDiag 3-19-23.txt	Download
Description	dxdiag file
Filesize	124 Kbytes
Downloaded:	67 time(s)

Filename	PD 3-19-23.mp4	Download
Description	vid w task mgr
Filesize	34189 Kbytes
Downloaded:	19 time(s)

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Steve1967

Newbie Private Message Joined: Mar 18, 2023 19:20 Messages: 7 Offline

Mar 19, 2023 09:24

Quote

In this case, since they just have a clip with no editing mods in the timeline to decode and apply, any form of Render Preview will make the clip larger and more complex to decode and playback.

Basic clip for NTSC timeline, 1920x1080, 4.79Mbps

For Render Preview:
Full HD Preview, 1920x1080, ~20Mbps
HD Preview, 1280x720, ~20Mbps
High Preview, 640x360, ~8Mbps

The timeline decode bitrate requires more computation for Render Preview at any preview quality setting and all are more demanding than decoding the basic clip, so the fact it didn't help is not at all surprising.

Additionally, other than the audio being demuxed which is advantageous, the audio can become more complex and larger depending on user timeline audio setting when using Render Preview.

Jeff

Thanks Jeff. I created a quick little clip with a few additional items in the timeline. Here it is, and I'd say the impact is even greater. I ran this with and without render preview without any noticeable difference. Task manager load maxed at 22%.

Apologies for being new to this forum. Is it acceptable here to post an actual file to see if others can replicate the issue?

Filename	Intro 3-19-23.mp4	Download
Description	Skipping w timeline edits included 3-19-23
Filesize	5253 Kbytes
Downloaded:	70 time(s)

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JL_JL

Senior Contributor Private Message Location: Arizona, USA Joined: Oct 01, 2006 20:01 Messages: 5802 Offline

Mar 19, 2023 10:25

Quote Thanks Jeff. I created a quick little clip with a few additional items in the timeline. Here it is, and I'd say the impact is even greater. I ran this with and without render preview without any noticeable difference. Task manager load maxed at 22%.

Apologies for being new to this forum. Is it acceptable here to post an actual file to see if others can replicate the issue?

Forum guidelines are here: https://forum.cyberlink.com/forum/posts/list/18337.page

I'd stay as far away from Render Preview as you can, it should not be a need on a platform as yours and often causes significant issues latter on in the editing/producing end of a real project. I was merely point out that if one had timeline fluidity issues with just a low-end clip in the timeline, using any form of Render Preview would not be expected to help. Likewise, I wouldn't expect your slight edited timeline to make much difference as something is basically amiss that you can't play back the basic low bitrate skateboard file on its own.

I’d probably update GPU driver to current (clean install, driver only) and then start looking at influence of your display resolution, PD preview quality settings, PD RGB vs YUV pref settings as a start. Your 10-15% CPU load for basic skateboard playback only on the timeline is very high on a i7-12700, especially if you have Hyper-Threading enabled regardless of how pref > Hardware Acceleration is set.

Jeff

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Steve1967

Newbie Private Message Joined: Mar 18, 2023 19:20 Messages: 7 Offline

Mar 19, 2023 10:52

Quote

Forum guidelines are here: https://forum.cyberlink.com/forum/posts/list/18337.page

I'd stay as far away from Render Preview as you can, it should not be a need on a platform as yours and often causes significant issues latter on in the editing/producing end of a real project. I was merely point out that if one had timeline fluidity issues with just a low-end clip in the timeline, using any form of Render Preview would not be expected to help. Likewise, I wouldn't expect your slight edited timeline to make much difference as something is basically amiss that you can't play back the basic low bitrate skateboard file on its own.

I’d probably update GPU driver to current (clean install, driver only) and then start looking at influence of your display resolution, PD preview quality settings, PD RGB vs YUV pref settings as a start. Your 10-15% CPU load for basic skateboard playback only on the timeline is very high on a i7-12700, especially if you have Hyper-Threading enabled regardless of how pref > Hardware Acceleration is set.

Jeff

Thanks again Jeff. I started hardware troubleshooting this morning and found that it works perfectly with an old 1080 monitor. It also works with the 1080 monitor and one of the 4K monitors, but fails if it is either one or both of just the 4Ks. I'll get to work on monitor drivers and settings and see where it goes. Appreciate all the help so far!

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Steve1967

Newbie Private Message Joined: Mar 18, 2023 19:20 Messages: 7 Offline

Mar 19, 2023 11:56

Ok, so I can produce and eliminate the failure at will now. Changing the timeline frame rate from 60 (default) to 30 or 24 eliminates the issue and permits both 4K monitors to work as expected. I still have problems with audio synching in other videos but I really don't know what frame rate they were shot at. Probably some more exploring to do with video where I know how it was shot and see how it reacts in PD.

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JL_JL

Senior Contributor Private Message Location: Arizona, USA Joined: Oct 01, 2006 20:01 Messages: 5802 Offline

Mar 19, 2023 12:43

Quote Ok, so I can produce and eliminate the failure at will now. Changing the timeline frame rate from 60 (default) to 30 or 24 eliminates the issue and permits both 4K monitors to work as expected. I still have problems with audio synching in other videos but I really don't know what frame rate they were shot at. Probably some more exploring to do with video where I know how it was shot and see how it reacts in PD.

Download and use MediaInfo or use the MediaInfo online https://mediaarea.net/MediaInfoOnline to get most pertinent details of a video stream.

Jeff

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Steve1967

Newbie Private Message Joined: Mar 18, 2023 19:20 Messages: 7 Offline

Mar 19, 2023 12:52

Last post - this one is fully solved. My monitors frame rate is limited to 30hz when using HDMI connections. Changing to display port cables increases it to 70 hz and everything plays well at all frame rates now. Sheesh.....

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