going slightly out of sync

[dawad]

running a video track with seperate voice track for audio (better quality) i edit using ripple edit
however sometimes the audio goes slightly out of sync and i have to keep correcting it
why is this happening?

[Ken Berry]

You don't give us much to work with such as the Properties of the video. Is any of the video, for instance, from a mobile phone camera? If so, and the phone is relatively recent, then it probably uses a variable frame rate rather than the constant frame rates that VS uses. So that would mean that video which is slightly slower or faster than the frame rate used by VS would kick the accompanying audio out of sync. But that's just one possibility. So give us some further information.

[lata]

Hi
Are all audio using the same kHz Sample Rate
“44.100 kHz, 16 Bit, Stereo” or maybe “48.000 kHz, 16 Bit, Stereo”

just a thought

[dawad]

1080 video at 30 fps and all audio are same sample rates.
i know this is not the problem since before i start chopping up the video with audio track running below it i can jump 20 minutes in and video and audio are perfectly in sync.
its just when i make a chop in ripple edit, from that point and on the audio seems to jump out of sync and i then i have to zoom into the audio track and just slightly move it back or forward a millisecond to put it exactly back in sync

[lata]

Hi
I don’t really understand why a sound clip would go 20 minutes out of sync, don’t really understand that

When you make a cut to the video, if we are in Project mode then all clips will be cut across the same timecode,
A second cut in Project and we could delete the selection, ripple editing will move clips to fill any gap.
Audio should be in sync, same as before the cut or at least should be.

If we do individual cuts in Clip mode we can select end if first clip or beginning of second, that cut will not be across the same timecode and would affect the sync by 1 or 2 frames a milli second, so you are best cutting all clips in one go

Other than that i am not sure what to suggest

[john4647]

I have a similar experience, not sure if it is the same thing.
I have been producing Video music quizzes for family and friends during the 'stay at home' period.
The procedure I use is to download a music video from say U Tube, then use Audacity to mute certain areas of the video.
Then, with VS, place the downloaded video onto the timeline and mute the audio.
Next, I place the Audacity version of the soundtrack on either Voice or Music track, taking great care to align correctly to the video.
This then, puts the audio slightly out of sync.
To correct this I move the Audio approx 1/2 second to the left (earlier than the video).
Each time this is about the same lag, not sure if it's a VS thing or an Audacity thing but in any case, not that serious.

[lata]

Hi John
Have you tried using VS for both clips, do you need both clips?
1 / add the video to the top track
2 / right click the clip for Split Audio, an audio clip will be placed on the voice track
The top track will be muted, you can undo that if you wish.
You can now cut the clips into sections allowing you to mute any section.

[john4647]

Hello Trevor,

I find that using VS to mute audio has two problems, first it does not totally mute, leaving an albeit much lower volume, the 'muted' part can still be heard.
Also the Sound Mixer in VS is a little vague to say the least.
I am quite happy using Audacity and adjusting the tracks, just wondered if I was doing something wrong.
This is the sort of thing I have been doing.

https://drive.google.com/file/d/1_81ARn ... sp=sharing

[lata]

Hi
Yes I realise that using the sound Mixer to reduce the volume that -36 can only be achieved
There is a Adjust Volume option from the options panel, or right click the clip. This defaults to 100, reduce that to 0 and as far as I can tell will mute the sound. Also available from the Music and voice tab.

I was thinking that if you use the scissors to cut a section that could be muted
Making a cut either side of “ MidNight Hour” then set volume 100 to 0 for that clip using the Adjust Volume option or for a video clip a right click for Audio - Mute

I noticed that if I first set Sound Mixer then adjusting the 100% option had no effect, I had to reset Volume to remove the -36 effect then changing 100 to 0 did mute the clip.
No need to use Sound Mixer at all

[john4647]

Thanks Trevor, I will give that a try on my next quiz.

[dawad]

Hi
I don’t really understand why a sound clip would go 20 minutes out of sync, don’t really understand that

When you make a cut to the video, if we are in Project mode then all clips will be cut across the same timecode,
A second cut in Project and we could delete the selection, ripple editing will move clips to fill any gap.
Audio should be in sync, same as before the cut or at least should be.

If we do individual cuts in Clip mode we can select end if first clip or beginning of second, that cut will not be across the same timecode and would affect the sync by 1 or 2 frames a milli second, so you are best cutting all clips in one go

Other than that i am not sure what to suggest

sorry didnt explain myself clearly. it does not go out of sync 20 minutes. thats just a method i use to check if both audio tracks are the same speed by jumping 20 minutes in.if they are not then 20 minutes down the line you we see they go way out of sync.
in my case they are still in sync even if i jump to the end so thats not the problem like those who bring audio from audacity etc.
all that being said, with everything perfectly in sync as soon as i make a cut using ripple edit i sometimes find my audio track going ever so slightly out from video track (by allowing both audio from video and seperate audio track recorded from voice recorder, to be heard) which is not hard to fix i just move it back a fraction or two but its very irritating and time consuming.
by the way i am recording lectures and i record audio seperately with a voice recorder since my camera has a lousy mic

[lata]

Hi
Thanks for that, makes sense

When you use the scissors if you are in Project mode the scissors will cut all timelines so top and voice tracks will be cut
If in Clip mode the only the selected clip will be cut, you then have to select the second clip to cut, that could cause a frame or two difference.

When the audio does drift out, by how many frames

[dawad]

Hi
Thanks for that, makes sense

When you use the scissors if you are in Project mode the scissors will cut all timelines so top and voice tracks will be cut
If in Clip mode the only the selected clip will be cut, you then have to select the second clip to cut, that could cause a frame or two difference.

When the audio does drift out, by how many frames

so yes i only use scissors in project mode which cuts all timelines as you said.
the audio on average will drift out 2 frames and i would say this happens about 75% of the time so i have to go into audio track, zoom in, and then hold left mouse button and carefully move it back 2 frames which is very fiddly.(is there an easier way of moving back of forward one or two frames?)side question)

[lata]

Hi
With the clip selected try Alt + Arrow key, left / right, should nudge the clip along timeline, one press for one frame

I’ll dig out a test file suitable for syncing and see what I get, may be tomorrow now

Have you tried using MCE to sync remove sections?

[lata]

I have just tried MCE and getting some bad results, but not had a problem in doing manually by cutting and deleting on the timelines