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Still Capturing Out-of-Sync Audio
We still have NOT found a solution to our sometimes out-of-sync audio. Here are the details:
Mac Pro, Leopard, AJA Io-HD, FCP 6, CalDigit S2VR Duo eSATA drives. When we first fire up the system, we sometimes capture BetacamSP video 7-frames out of sync. This is not a playback problem…it captures the clip out-of-sync. This almost always happens with a “cold” system. Once everything warms up, it usually works fine, but not always. Once we notice out-of-sync clips, we can throw away the bad media from the scratch folder, and do a batch recapture, and it usually works fine.
It has captured out-of-sync with 8-bit uncompressed and DVCPro50 codecs. It has captured out-of-sync with both FCP and AJA VTR Exchange programs controlling the capture process. The Io unit has up-to-date drivers and firmware.
I do NOT think it is the AJA Io-HD unit because we switched Io boxes, and still had the same problem. I do NOT think it is Final Cut Pro related, because we captured bad media with both FCP and VTR Exchange.
This has been a difficult problem to chase down, mostly because it is intermittent. About the only consistency we’ve been able to establish is we tend to have the most problems on a “cold” system. But we have had some problems after the system has been up and running for several hours.
Oh yes….please don’t tell me to uncheck the high quality audio scrubbing box. That has nothing to do with this.
I’m at whit’s end. Any sugesstions?
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18 Replies
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Do you have any other capture device besides the ioHD and you have swapped the fw800 cable?
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No other devices. In fact, this is brand new system that has never ever had any other input devices on it, so there is no chance that some rogue left-over driver is causing us problems.
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I was just seeing if you had another device to capture from and see if it’s the ioHD or not.
And the fw800 cable, swapped it?
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> I’m at whit’s end. Any sugesstions?
Your debugging doesn’t follow a logical progression that i can tell, too many variables, but I’m only going on your description and I’m sure you think you’ve been conducting careful tests. Debugging problems like yours is a stupid binary process, boring, and mind-numbing. It requires a carefully planned scientific approach and the discipline of an accountant. You can only change one thing at a time and you must take scrupulous notes or you will never figure it out.
A “cold system” is meaningless in digital unless there is a device in the signal path that is somehow sensitive to physical influences. Once your signal leaves the conversion box/card, it’s going down a FW cable or bus as data and there is no way for audio to be separated from video to become out of sync.
How do you actually know these clips are out of sync? I’m asking because so many things can influence how married media files appear to play back. And I’m not watching you work nor do I have any idea how your system is built and I’ve never used this Io thing of yours.
When you capture, as opposed to digitize, all you are doing is transferring files form tape to the drives. They must be in sync if they were shot that way.
When you digitize, software in your box/card converts on the fly from the native to your capturing format. Once you eliminate capturing as a possible problem, digitizing is the only possible place your problem can be.
bogiesan
This is my standard sigfile so do not take it personally: “For crying out loud, read the freakin’ manual.”
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Are both the Beta Deck and the IO hooked up to the same Sync Generator?
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Dave, I know the clips are out of sync because they play back out of sync….in both Final Cut and in the basic Quicktime player.
I first considered the AJA Io-HD to be the primary suspect. But we had an extra Io (in an unopened box) that had not been installed on another system. When we replaced one Io with another, and we still had the same problems, that tells me one of two things: either the Io is NOT the problem, or all Io units share the same design fault that causes this problem. Since I have not been reading about this problem with other Io users, that second conclusion is kind of hard to believe.
Is this a Final Cut Pro problem in digitizing BetacamSP video? I don’t think so, because the problem came up when we digitized with both FCP and VTR Exchange.
So now I’m to the point where I don’t think the problem is with the Io-HD. I don’t think it is with Final Cut Pro. So could it be some sort of Mac Pro/Leopard issue? Could it possible be a drive issue, or made an eSATA host adapter card issue?
Why does this problem commonly show up when we first fire up the system? That has really been the only “most-of-the-time” consistent behavior we’ve noted.
The next thing we’re probably going to try is swapping out the CalDigit Fasta 4e eSATA host adapter card.
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Devin,
Yes…both the Io-HD and the Beta deck are hooked up to the same Horita BSG-50 black burst generator.
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[Tim Allison] “When we replaced one Io with another, and we still had the same problems, that tells me one of two things: either the Io is NOT the problem, or all Io units share the same design fault that causes this problem.”
Okay, did you uninstall and reinstall the proper drivers for this? io drivers and ioHD drivers are totally different.
Please give more info on where your PCI cards are placed in the system, and what else is connected to your MacPro.
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If you trashed your prefs did your system start capturing to the boot drive? That’s what I found last time this happened to me.
Jim Calahan
KVIE, Sacramento -
> Dave, I know the clips are out of sync because they play back out of sync….in both Final Cut and in the basic Quicktime player.
I know you wnat this fixed, patience.
Out of sync is only an artifact of the playback at this point; it does not indicate anything about the file itself, not necessarily.
Does the sync drift over time? If so, you’ve got a digitizing software error, probably bad EPROMs on the card. Should be an easy fix from Io.
> So could it be some sort of Mac Pro/Leopard issue? Could it possible be a drive issue, or made an eSATA host adapter card issue?
I do not see how. Never heard of it before your post and the Io seems to be popular. We’d have heard it before.
> Why does this problem commonly show up when we first fire up the system? That has really been the only “most-of-the-time” consistent behavior we’ve noted.
Physical changes to hardware are almost impossible to nail. but there simply is nothing I can think of that would cause audio to change processing speed or file creation sequence placement. This stuff either works or it fails. Usually.
> The next thing we’re probably going to try is swapping out the CalDigit Fasta 4e eSATA host adapter card.
This implies the audio and video are going to separate file locations. If the files are interleaved as one, the issue must be the digitizing hardware/software. That is, there is no way AFAIK that the video and audio files can be delayed after digitizing.
I can’t offer anything else of value, wishing you lots of luck, though. I’m certain this is going to be a real head-slapper (doh!) when you figure it out.
bogiesan
This is my standard sigfile so do not take it personally: “For crying out loud, read the freakin’ manual.”
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