Dropouts...

[Kelly M. Pieklo]

I've been working at this for a while and can't quite figure it out. I work with post - A/V Option, Machine control, 2 X 888/24, Mac G4 w/384 megs, Avid Media Dock tower w/6 iS9 9gig drives (SCSI). When doing translations (English to Spanish), I'm recording VO with picture playback simultaneously. Upon playback, I hear sporadic dropouts - usually between words. I first noticed this issue when I'd record the audio directly to one of the Avid Dock drives - talked to Digi, suggested recording directly to HD of G4, transfer to SCSI drives for storage, and mix from there. Unfortunately, I still have the problem. One thing I've noticed upon playback (with video) is slight pauses of the main counter - it stops for a split second, long enough for me to notice that the counter is choking (the video doesn't choke as far as I can see). The counter choke hasn't any regularity to it - it happens randomly. Could this be my drives accessing the video, holding up the audio recording thus causing the hiccup? I know it sounds complicated, and clients don't necessarily hear it, but it bugs the crap out of me. Any help appreciated - thanks.

[trakbytes]

Here's something to check-are you recording video and audio to the same drive? I have had trouble with this in the past. If not, are you using the same SCSI bus for both video and audio? This can put a heavy load on the SCSI transfer rate, and may cause interupts.

I usually load video to the internal IDE drive and audio to a SCSI drive to keep the data streams totally seperate. I did run into the "dropout" problem a couple of weeks ago when recording to a firewire drive. It just couldn't keep up, and I had random dropouts in the track, but no "9073" errors. Don't know if you've tried this, but I can't use firewire at all to record AV option video. It just crashes out immediately.

rcm

[Kelly M. Pieklo]

Thanks for the heads-up on the FWire drive and video - I haven't tried it but it sounds like it might not be worth it. As far as pushing the SCSI too hard - when recording audio and video off of tape (DBeta, SP, etc.) simultaneously, no dropouts in audio. Only when I'm tracking a vo w/picture (already on video drive) - and the dropouts only occur in the vo track, not any of the original on tape tracks that were captured with the video. In the waveform I can see the dropout, forcing me to believe that it's happening while tracking. Any other ideas? It couldn't be that I'm recording audio to my internal drive while accessing video from a SCSI drive, could it? That doesn't sound like it would cause a problem.

[Kelly M. Pieklo]

Another question - are you using AVOption or XL? I'm using AVOption and it sounds like Digi will only be supporting the XL for PT6.0. Any thoughts?

[DigiTechSupt]

Kelly,

Is Pro Tools slaved to incoming code while recording? Are you using MachineControl? Could be a frame rate mismatch.

If not that, it could be a million different things (extension conflict, clock problem, wrong slot order, etc.). You may want to give tech support a call and we can go through the whole system.

-Jordan

[Kelly M. Pieklo]

Yep - using Machine Control sync'ed to Serial time code via 9pin. Never have any trouble with that. I'm not syncing anything when recording my vo track - just playing video out of my PT system (off of SCSI drives).

[trakbytes]

I'm using AV option with PT 5.1.3 on a Mix +. And there is no way I plan to spend the $$$$$ for an upgrade to AV-XL. Will probably go with an ATI 8500 and capture Quicktime with a Miro card on and old 9600 machine. Probably will go to PT 6 at some time, but right now the problems outweight the (any?) benefits.

Back to your problem-Have you tried putting the video on the internal drive and recording audio to the SCSI? The SCSI is more robust. In any case, 1 channel of audio recording with video playback should not tax the system to the point of dropouts. How's the SCSI termination? Wide to narrow removables or LVD drives on a single-ended card? Seems like some kind of data throughput problem. I'd imagine you've ruled out any kind of intermittent audio connection...

rcm