baffled by sync problem in FCP 5.0

Hi All,
I'm having a bizarre sync problem on capture and would be grateful for any wisdom...

Here's the system I'm using...
FCP 5.0
QT 7.5.5
OS 10.5.5
MacPro w/ 2 x 3 Ghz Dual Core Xeon processors

When I capture, everything is waaaaaay out of sync. It doesn't seem to drift - seems to stay the same amount out of sync from start to finish of the clip, regardless of the length of the clip. I watch the clips as they digitize, and they look fine. But then they are out of sync in FCP and also out of sync when I open them directly in quicktime.

I should add that I am new to FCP 5.0 (yes, I am still in the dark ages and was working on 4.5 until very recently) and when I capture these clips, when it gets to the end of a capture, it brings up a window that says "validating audio data" - something I have never seen before in FCP.

I tried trashing my prefs - no difference.

I tried capturing to my internal drive instead of my externals - no difference.

I tried using capture now instead of batch capture - no difference.

I double checked my audio/video settings to make sure that I am watching the clips on my computer and monitoring audio through the computer's built-in audio - still out of sync. Also tried watching/listening via firewire output through my deck/external monitor - still out of sync.

I'm stumped. Any ideas what could be causing this? Many thanks for your advice.

1st thing i notice is that youre running a way old version of fcp on the newest mac operating system...

I think Wayne's onto something. I don't think that old of a version of FCP even knows what an Intel processor is, let alone how to play nice with it.

You may be stuck upgrading.

deb

Could be an issue with FCP/QT mismatch. BUT, you could try the usual troubleshooting steps too...

Usually when there's an issue with sync, it is caused by a sample rate mismatch. The sound guy could have been recording at 32khz (not adviseable, but it may just have happened). Try capturing with audio set to 32khz instead.

Here's how:

[support.apple.com]



www.strypesinpost.com

Yeah, I was worried it might be some kind of weird incompatibility between old FCP and new system/quicktime. Sigh...

Just for kicks, I tried capturing the audio at 32K (even though I know it was recorded at 48K because I recorded it myself and have captured/cut with it before)... it was interesting. Capturing at 32K, it was much closer to being in sync, but it still wasn't dead-on. (like, it's now about 3-4 frames off, as opposed to being a second off.)

If anyone runs across a similar problem (and comes up with a good solution for it), I'd still love to hear about it!

>it's now about 3-4 frames off, as opposed to being a second off.)

Sync drift? Is the audio constantly out of sync, or does it drift further off sync? DV allows 2 sample rates- 32 and 48khz, so you may have nailed one of it. Next, I'm not in an NTSC country, so I'm no authority on this, but I am wondering if NDF and DF has anything to do with it.

Otherwise, 48khz is highly recommended for use because the audio is locked to the picture. This prevents sync drift.



www.strypesinpost.com

No, it's not drifting. It seems to be consistently out of sync, regardless of the length of the clip (or where in the clip I look at it). And a few of the tests I've done have been long ones. (20-30 min. clips).

I also don't think it's a NDF/DF issue. All my capture/deck settings are correct, and I've also confronted NDF/DF problems before (in my past life as a sound editor). But I've never come across something this far out of sync when that's the problem.

Another thing I should note: when I captured at 32K, the little window that says "validating audio data" did not come up at the end of the capture, as it did when I was capturing at 48K. Does anyone know anything about that message? I tried searching the archives for info on it, and found one case similar to mine. But that's a new one that I've never seen before, and I can't find any reference to it in the FCP manual. Not sure where it's coming from or what it means.

It sounds the audio was in fact recorded at 32khz. Time to call the sound recordist and give him a verbal bashing. Okay. Actually try it on a newer system if you have access to one and see if the problem reoccurs there.

Does the sound slip noticeably off even after 5 minutes? It sounds like you're running a capture now. Using log and capture, capture in small portions and convert the audio to 48khz in Quicktime.

>I can't find any reference to it in the FCP manual

DV specs. 48khz allows "locked" audio, which means that every specific amount of frames (think it's 5 frames for NTSC and something else for PAL), the audio is "locked" to a specific sound sample.



www.strypesinpost.com

I don't know how the heck you got that to work. You're supposed to use 5.1.4 or better on any MacPro. You're looking at an unsupported setup.

You need the upgrade your Final Cut Studio or move to another machine with that software.

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