14 Replies Latest reply: Jul 17, 2012 7:03 AM by Stephen Fuchs
Studio Engineer Level 2 (445 points)



Forums and blogs are overflowing with folks having stutter-Problems with FCPx. I am one of them.


1 reason for stutter is if you have not recorded sound with the video file. FCP will stutter if the clip is played back with no audio in the timeline.


2 - This is the most conniving feature/bug I have ever experience in any software.


I have a very fast Mac with a RAID0 capable of of R/W of 490MB/s - I dont have any problems playing back anything from an H.264 to a DPX Image Sequence. 32 GB of RAM and NVIDIA qualified Card.


Today again, I am experiencing random stutter when playing back the timeline (even though it has audio).

It doesn't matter whether I set the playback preferences to better performance or higher quality. Same problem.

FCPx wont even report the frame drops although I have that option enabled.


Here is how to rid yourself of stutter, that does NOT pertain to your mac being under-powered.


Simply Place your skimmer (Mouse Cursor) on/over any clip before hitting play. Let it sit there until your are done viewing.

If you move it (while it is there) you are likely to get frame drops.


If you place the skimmer ANYWHERE (in the gray parts of timline) where there is no clip, FCPx is NOT able to playback smoothly.

And will stutter. At least on my 3 setups.



This IMO is insane.


Nevertheless, this is a sure workaround with my setup.


30 Inch Cinema Display

Mac Pro 2.26 8 Core Nehalem

32 GB RAM - RAID0 (4 Drives)

I work with FullHD/48khz Stereo/Canon .MOV Files.



If anyone has ANY idea why this happens - please let me know

  • Tom Wolsky Level 10 (115,500 points)

    If I put the skimmer over a gap clip and play, the playhead rolls into the play and there is no stutter. I don't think starting on a gap clip is a cause.


    What's FullHD mean? What are the project properties? What's a Canon .mov?

  • Studio Engineer Level 2 (445 points)

    1 = FullHD = 1920x1080

    2 = 1080p HD | 1920x1080 | 25fps

    3 = H.264 from 5DMKII (Matters not - whether I choose to create opt. media. Stutter is there if the mouse is NOT parked on a clip while playing)



    Put the skimmer/mouse over any clips with video on it. Hit the home key, to go to beginning of Timeline, hit play.

    Stutterfree. If I place the mouse ANYWHERE else than on a clip, my playback will stutter like a sick horse.

  • Tom Wolsky Level 10 (115,500 points)

      Just to be clear, if the pointer is here, as in this picture, the video will stutter on playback?




    Not seeing that.

  • Studio Engineer Level 2 (445 points)

    Yes Sir....


    Placing it on a clip will (before hitting play) will make it playback smooth as a baby...


    After discovering this I even hooked up my second display and am placing the viewer on there in fullscreen.

    I have playback settings to high quality. And FCP does NOT yeild a single hickup. Moving the skimmer to the area in your screen shot above will immediately cause FCPx to stutter...


    Thanks for taking the time to chime in....

  • Tom Wolsky Level 10 (115,500 points)

    Verty strange. I'm not seeing that all with H.264 1080p30. I wonder if it's the second monitor that causes it.

  • Studio Engineer Level 2 (445 points)

    Dont think so... I discovered this before attaching it....



    Perhaps it pertains to the fact that my H.264 files have no audio recorded to them.

  • Tom Wolsky Level 10 (115,500 points)

    Could be, though that would be strange.

  • Luis Sequeira1 Level 6 (9,515 points)

    I have experienced this "stuttering when there is no audio" too, this past weekend, and in a very simple project. One clip, less than a minute long.


    In my case, it was different, in that the clip did have audio, but in a part of the clip the audio had been turned all the way down (using keyframes). The part with audio "on" played normally, the part with audio "off" stuttered.

    Adding a music track below the clip eliminated the stuttering.

  • Studio Engineer Level 2 (445 points)

    Yes... I can confirm this too...


    If I load up my clips with no audio into the timeline, stuttering is there immediately.

    Then I add an audio track to the timeline and the stutter vanishes.


    Then, if I turn down the volume of the audio to zereo or - 46 dB. The stuttering reappears.


    If, however, I place the cursor (Skimmer) in a clip prior to hitting play, the stutter vanishes yet again...


    I adore FCPx and after getting to know it, there really is NO going back for me. This app is more than a decade ahead of its time and it's new. And still in a sort of beta-phase. At least that is what I tell myself so that I can deal with it ;-)


    At least now we know ONE reason why stuttering appears and by identifying the problem, we can solve it !

  • Paul Cuciti Level 2 (385 points)

    Has anyone tried pressing 'S' to turn off skimming?

  • innocentius Level 4 (1,880 points)

    I can confirm this, I had  some clips with lot of effects and saw small stuttering. Just added a soundtrack and the stutter disappered. I find this amazing

  • Penn-Ohio Level 1 (0 points)

    "Studio Engineer" are you using 10.0.3 or 10.0.4?

  • Stephen Fuchs Level 2 (305 points)

    I am experiencing this same exact issue running 10.0.5.  I even tried bringing in a aiff audio file that had no actual sound and FCPX began stuttering.  It isn't an issue with there not being an audio clip, it has something to do with the volume.

  • Stephen Fuchs Level 2 (305 points)

    Has anyone been able to find a solution to the stuttering with no or reduced audio bug?