First, the tech specs:
iMac 27" mid-2011
2.7 GHz Core i5
20 GB RAM
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:
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.