I've looked this up on the forum but all the answers I got where from past version (MC4 or earlier) and all for PC, and after trying most of them that could apply on a mac, the problem still persists.

Basically I have a bunch of XDcam clips linked to AMA, most of them work fine, but every now and again, I come across a clip that won't playback in both the source monitor or when I put it in a timeline... i can scrub through the clip and see the images, but during playback the clip goes black and only the audio plays back.

I have heard this could have to do with my graphic card driver, but on this station, an iMac machine, I can't manually update the driver like on a windows machine, it has to come through an OSX update (which my system is up to date with 10.8.2). this system also complies with the qualified hardware list, it is a iMac mid 2011, 27" display, 3.4GHz i7 Quad core with ATIRadeon 6970M and 16Gb of RAM. The problem file are all on a firewire800 RAID (in RAID-05 mode) and just to add I have tried moving the files to a different location (including the system drive and an other external drive) with no change.

the only thing I've noticed that all these file have in common is the fact that they are large clips, and so their names are in the style of 454_2040 instead of the other files which all have names like  454_2040_01 (the 01 at the end is the difference). As I understand it, in the XDcam file structure format, this implies that this clip is comprised of a number of smaller sub clips on the card the camera automatically generates when a clip goes beyong the 4Gb file size. Avid, just like the Sony clip browser, reassembles these parts when linking to the file into one single clip.

I have managed to work around this problem by relinking the files to AMA a second time, which usually solves the problem... for a while... but every now and again it comes back, so finding a more permanent solution would be good...

anyone else having similar issues with large XDCAM files?

thanks for any help or suggestion

just to add, I've found another piece of the puzzle... frame rate. the clips I mentioned where 1080p 29.97, but my project was set at 1080i 59.97 so I could use my blackmagic intensity box, and the final output will have to be in 1080i (for broadcast). So I switched the resolution to 1080p and all the problem clips now work fine. Practically everything whe shot for this project was 1080p, and except these problem clips they all played fine with the system set at 1080i, so I still think there is an issue here that should be addressed... albeit a little less urgent now.

I hae a similar issue.  When I move the timeline marker up and down the timeline, the clips don't refresh so there is a trail of blue lines left on the clips.

If I do something to cause the entire timeline to repaint, the trail of blue lines goes away.

I tried changing the project settings as noted above, but that didn't do anything.

System:

Win 7 sp1

i7 processor

NVIDIA Geforce GTX 660 Ti driver number version is 9.18.13.568 dated 8/8/2012

Other than this issue all other video functions seem to be stable and working just fine.

Pierre Paré-Blais:

I have a bunch of XDcam clips linked to AMA, most of them work fine, but every now and again, I come across a clip that won't playback in both the source monitor or when I put it in a timeline... i can scrub through the clip and see the images, but during playback the clip goes black and only the audio plays back.

Pierre,  I am having the same issue using clips shot at 1080i 29.97.  I too have found that if I change the project format to 1080i 59.94 the video plays back.  Did you ever find a resolution for this issue?  If so could you share it in detail?

Matt