capturing audio out of sync? at DVinfo.net

Matt Fowler · February 9th, 2010, 06:04 PM

I use fcp 3 and when i capture my audio is out of sync? Any ideas?

William Hohauser · February 9th, 2010, 07:21 PM

Don't capture to the system drive. Use a fast external drive, FireWire not USB. Make sure you have enough spare room on the drive, a packed and fragmented drive won't capture as well even if it has enough space. Make sure you are capturing the audio with the same khz as the capture codec, 32000 or 48000. Check to see if you are capturing over a scene break or if there is drop-out on the tape. All of these things can cause a problem.

Matt Fowler · February 9th, 2010, 10:36 PM

Could it be the mic i'm using?
A wired lapel on about a 20' xlr?

William Hohauser · February 10th, 2010, 12:52 PM

Not really possible. See if your on-camera mike has the same problem. I think it's related to the capture process. Do all tapes capture badly?

Matt Fowler · February 22nd, 2010, 09:14 PM

I checked the capture just using the on camera mic and there still out of sync? any ideas?

William Hohauser · February 23rd, 2010, 10:10 AM

Do the files play out of sync in QuickTime Player?

Please tell us you system setup, computer, drives, etc.

Michael Liebergot · February 23rd, 2010, 10:29 AM

I had the same problem with FCP before.
The solution for me was to trash the preferences and restart FCP.

Cleared the sync issues up right away.

I have found when FCP starts to act wonky, a simple preference trashing solves the problem.

BTW, the captured audio was not out of sync in the trimmer or while played in QuickTime, it only played out of sync on the FCP timeline.
But trashing the preferences fixed the problem.

Matt Fowler · February 23rd, 2010, 04:25 PM

I played it in quicktime and it was out of sync there as well.
Setup:
Mac g3 9.2.2
fcp 3
Calvary 1 TB External firewire
Sony PD 170

Matt Fowler · February 24th, 2010, 09:17 PM

i did some more testing today.
I can capture a live video signal from a camera (not off a tape) and the audio is in sync but when i put a tape in the same camera to capture its way out of sync.

William Hohauser · February 25th, 2010, 03:22 PM

Might be the tape deck in the camera although I've never heard of this before. Has it ever been dropped?

Matt Fowler · February 25th, 2010, 08:20 PM

I tried capturing from tape on a canon hv20 and it had the same affect out of sync.

Matt Fowler · March 1st, 2010, 11:00 PM

I dont have anymore ideas on whats wrong its off by several seconds?

Nigel Barker · March 2nd, 2010, 01:33 AM

Quote:

Originally Posted by Matt Fowler

I played it in quicktime and it was out of sync there as well.
Setup:
Mac g3 9.2.2
fcp 3
Calvary 1 TB External firewire
Sony PD 170

Has it ever worked with the audio properly synchronised? No disrespect but that is a very old & slow system. My iMac G3s are just very large novelty paperweights now.

R Geoff Baker · March 2nd, 2010, 08:51 AM

Truth be told, almost any old system can capture a 25Mb/s stream -- I have an ancient (ten years old!) PC that I use to capture, then transfer to my Mac for editing. (Mostly because I really really like Scenalyzer Live for capture)

If the file is in sync in Quicktime, it would be an FCS prefs problem -- but your problem starts earlier. Out of curiosity I'd try the captured file in a player like VLC to see if the issue is with the file or with the playback configuration -- if the VLC player handles it properly maybe a reinstall of QT is in order.

It is technically very difficult for the audio and video to be out of sync -- the Firewire transfer is a muxed file, with the two components interleaved ... quite how the transfer could get out of sync I can't imagine.

Cheers,
GB

William Hohauser · March 2nd, 2010, 10:03 AM

Actually, I've had this problem with an old G4 computer which I was using mainly for capture and it wasn't worth the time to figure out the problem as I had a fallow G5 sitting around which worked fine. I'm sure if I wiped the entire G4 and reinstalled only the OS and FCP it would have worked better. But who knows, maybe the capture hard drive was on it's way to failure. I've also had problems with audio sync on playback on all my machines when Time Machine kicks in so I now have it set to manual backups.

The curious issue is how a live camera capture is in sync but tape playback isn't. Since the FireWire video data stream is identical in both instances the only variable is deck control. Does a non-controlled tape capture suffer the sync issue?

February 9th, 2010, 06:04 PM	#1
Matt Fowler Regular Crew Join Date: Dec 2009 Location: Kansas Posts: 54	capturing audio out of sync? I use fcp 3 and when i capture my audio is out of sync? Any ideas?

February 9th, 2010, 07:21 PM	#2
William Hohauser Inner Circle Join Date: Dec 2005 Location: New York City Posts: 2,650	Don't capture to the system drive. Use a fast external drive, FireWire not USB. Make sure you have enough spare room on the drive, a packed and fragmented drive won't capture as well even if it has enough space. Make sure you are capturing the audio with the same khz as the capture codec, 32000 or 48000. Check to see if you are capturing over a scene break or if there is drop-out on the tape. All of these things can cause a problem. __________________ William Hohauser - New York City Producer/Edit/Camera/Animation

February 10th, 2010, 12:52 PM	#4
William Hohauser Inner Circle Join Date: Dec 2005 Location: New York City Posts: 2,650	Not really possible. See if your on-camera mike has the same problem. I think it's related to the capture process. Do all tapes capture badly? __________________ William Hohauser - New York City Producer/Edit/Camera/Animation

February 22nd, 2010, 09:14 PM	#5
Matt Fowler Regular Crew Join Date: Dec 2009 Location: Kansas Posts: 54	Still having problems I checked the capture just using the on camera mic and there still out of sync? any ideas?

February 23rd, 2010, 10:10 AM	#6
William Hohauser Inner Circle Join Date: Dec 2005 Location: New York City Posts: 2,650	Do the files play out of sync in QuickTime Player? Please tell us you system setup, computer, drives, etc. __________________ William Hohauser - New York City Producer/Edit/Camera/Animation

February 9th, 2010, 10:36 PM	#3
Matt Fowler Regular Crew Join Date: Dec 2009 Location: Kansas Posts: 54	Could it be the mic i'm using? A wired lapel on about a 20' xlr?

February 23rd, 2010, 10:29 AM	#7
Michael Liebergot Trustee Join Date: Jan 2005 Location: Maryland Posts: 1,505	I had the same problem with FCP before. The solution for me was to trash the preferences and restart FCP. Cleared the sync issues up right away. I have found when FCP starts to act wonky, a simple preference trashing solves the problem. BTW, the captured audio was not out of sync in the trimmer or while played in QuickTime, it only played out of sync on the FCP timeline. But trashing the preferences fixed the problem. __________________ Michael www.lvpvideo.com

February 23rd, 2010, 04:25 PM	#8
Matt Fowler Regular Crew Join Date: Dec 2009 Location: Kansas Posts: 54	I played it in quicktime and it was out of sync there as well. Setup: Mac g3 9.2.2 fcp 3 Calvary 1 TB External firewire Sony PD 170

February 24th, 2010, 09:17 PM	#9
Matt Fowler Regular Crew Join Date: Dec 2009 Location: Kansas Posts: 54	i did some more testing today. I can capture a live video signal from a camera (not off a tape) and the audio is in sync but when i put a tape in the same camera to capture its way out of sync.

February 25th, 2010, 03:22 PM	#10
William Hohauser Inner Circle Join Date: Dec 2005 Location: New York City Posts: 2,650	Might be the tape deck in the camera although I've never heard of this before. Has it ever been dropped? __________________ William Hohauser - New York City Producer/Edit/Camera/Animation

February 25th, 2010, 08:20 PM	#11
Matt Fowler Regular Crew Join Date: Dec 2009 Location: Kansas Posts: 54	I tried capturing from tape on a canon hv20 and it had the same affect out of sync.

March 1st, 2010, 11:00 PM	#12
Matt Fowler Regular Crew Join Date: Dec 2009 Location: Kansas Posts: 54	Still having sync issues!!! I dont have anymore ideas on whats wrong its off by several seconds?

March 2nd, 2010, 08:51 AM	#14
R Geoff Baker Major Player Join Date: Jan 2005 Location: Ottawa, ON Posts: 471	Truth be told, almost any old system can capture a 25Mb/s stream -- I have an ancient (ten years old!) PC that I use to capture, then transfer to my Mac for editing. (Mostly because I really really like Scenalyzer Live for capture) If the file is in sync in Quicktime, it would be an FCS prefs problem -- but your problem starts earlier. Out of curiosity I'd try the captured file in a player like VLC to see if the issue is with the file or with the playback configuration -- if the VLC player handles it properly maybe a reinstall of QT is in order. It is technically very difficult for the audio and video to be out of sync -- the Firewire transfer is a muxed file, with the two components interleaved ... quite how the transfer could get out of sync I can't imagine. Cheers, GB

March 2nd, 2010, 10:03 AM	#15
William Hohauser Inner Circle Join Date: Dec 2005 Location: New York City Posts: 2,650	Actually, I've had this problem with an old G4 computer which I was using mainly for capture and it wasn't worth the time to figure out the problem as I had a fallow G5 sitting around which worked fine. I'm sure if I wiped the entire G4 and reinstalled only the OS and FCP it would have worked better. But who knows, maybe the capture hard drive was on it's way to failure. I've also had problems with audio sync on playback on all my machines when Time Machine kicks in so I now have it set to manual backups. The curious issue is how a live camera capture is in sync but tape playback isn't. Since the FireWire video data stream is identical in both instances the only variable is deck control. Does a non-controlled tape capture suffer the sync issue? __________________ William Hohauser - New York City Producer/Edit/Camera/Animation