audio blanking out when exporting from FCP or QT proxy

[zoltan77]

Hi,

I'm doing post on a RED job and trying to get my head around this bizarre audio problem.

The clip in question is an hour long interview and when I drag the 'P' quicktime proxy into FCP and place on a timeline everything plays fine the whole way through the clip. But as soon as I try to export the timeline to another quicktime (which I need to do because I've added timecode burn-in so it can go out for transcription), the audio cuts out about 15 mins from the end of the clip. The strange thing is if I go to the point where it cuts out in the FCP timeline, it plays just fine all the way to the end.

I've tried just about everything I can think of - turning off one track and exporting in case it's phase cancellation, using export 'quicktime movie', 'quicktime conversion...' and 'Audio to AIFF(s)', exporting in quicktime player pro directly from the quicktime proxy, all to no avail. no matter what I do, the audio always goes silent at the exact same place around the 45min mark in the exported clip. Worst case scenario, I could hook up a DAT or some other device to my Kona outs and record FCP playing the timeline out in realtime, but that seems silly, not to mention time consuming.

I tried opening some of the .R3D files in red alert but the image isn't even showing up for some reason when I scrub through them, plus it's not clear to me how I would string all the raw files together to export audio for the whole sequence in any case.

I'm on FCP 6 and afaik I have all the latest RED codecs, red alert, etc., installed from the RED site.

Any help you can provide would be awesome as I have an antsy director pacing through the office

 

[Noah Kadner]

Yeah that sounds like a spanned clip issue. Do you have absolutely all of the original R3D files on this system so they can be accessed directly in QT? Confirm that the footage is really all online. Also try trimming the clip to the 45 minute mark in QT Player and exporting an AIF from there. Also confirm that the audio really in there up until the end of the clip.

Noah

 

[zoltan77]

cool, thanks for the quick reply.

yeah, tried most of that. right now I'm copying over all the raw footage to a local drive in case it's something weird with not being on my system raid, but I doubt it. Next to try is outputting from red rushes, but unfortunately it does not seem that you can output only audio from RR (would be great feature, hint, hint), but have to do some format of video which means something like 12-24hrs of rendering just to get a qt.

For now, can't wait, dubbing out to DAT from my timeline in realtime and then back in. It's not right, but it works (hopefully). Weird thing is I already heard some white noise bursts for a few seconds at one point coming off the headphones as if the audio itself is corrupted in some places. Will try red rushes next week when I have more system downtime to confirm if that is an option to fix in the future, and/or fix those bursts.

Long term solution is probably to not to record 1hr takes. Of course both audio guy and red tech told director not to do it... but he did... Also dual system sound for backup seems like a good idea w/ red too.

thanks again