0 Replies Latest reply on Jul 15, 2013 12:00 PM by scottauerbach

    sync problems - skipped and repeated frames - longstanding problem

    scottauerbach Level 1

      First, the tech specs:

      iMac 27" mid-2011

      2.7 GHz Core i5

      20 GB RAM

      RadeonHD 6770M

      OS 10.7.5

      Premiere CS6

      Promise R4 RAID 5 attached via Thunderbolt

      Blackmagic UltraStudio Express

      Additional 27" Thunderbolt monitor





      About a year or so ago, I bought CS 5.5 as a FCP switcher.  Installed it on a brand-new iMac, along with Avid MC6.  I found I was consistently having problems with sync "hiccupping" during playback, so I back-burnered my transition to Premiere, and kept working on my old Mac Pro with FCP.


      When the upgrade to CS6 came along, I thought "Okay, maybe that'll fix the problem."  It didn't.  I started working with it on small projects where the client wasn't in the suite, and the skipping/stuttering wouldn't drive me too crazy.  Over time, I've tried everything imaginable, and nothing has solved the problem. I'll list some of the things I've tried below:


      Uninstalled CS5.5

      Uninstalled Avid

      Switched from AJA to Blackmagic

      Tried different drives

      Tried the Promise on a different Thunderbolt port

      Made the Promise the first peripheral on the daisychain

      Checked whether file format / frame rate / data rate makes a difference (it doesn't -- even 720p ProRes 422 won't play smoothly for long)

      Tested the same files / sequences on FCP (they play flawlessly)

      Speed-tested the Promise RAID array (>350 MB/sec read/write speeds)

      Removed the second monitor



      Both audio and video have occasional glitches, though the video glitches are far more obvious. I'm posting a screencap on YouTube (no audio) that shows the video stuttering quite clearly. The worst examples are at :26, 1:02, 1:45, though you'll see small glitches at other spots, too.


      Audio and video do not tend to glitch at the same time, and there's nothing repeatable about when the skips/repeats occur.  Exported files are clean.


      In terms of possible software conflicts, there's very little on my machine, and everything on there is pretty standard-issue edit suite stuff: Microsoft Office, RED Cine X, PluralEyes, etc.


      Screencap movie is on YouTube at




      Another problem I've had --which I'm not demonstrating in the screencap-- is audio sync drifting more and more out of sync on playback of RED 5k .R3D files, even when playing back from a direct-attached Thunderbolt RAID and RED Rocket card (in Sonnet Echo external chassis). When I hit the space bar and re-start playback, it starts off in sync, then starts drifting out again. This despite the fact that Premiere touts its ability to work with R3D (in lower-res mode) without even using the Rocket card.  I've tested this both at full res with the Rocket card, and at as low as 1/8 res without the Rocket card enabled.  Sync always drifts. 


      Any advice would be appreciated... There's no way I'll move to CC unless I can solve this problem.

      Scott Auerbach

      Sputnik Pictures