Phoenix cards = stuttering

I'm getting a stuttering or intermittent lag with the Phoenix cards in my servers. The problem does not manifest itself constantly; cameras will be fed through the system smoothly but then every so often (maybe every 30-60 seconds) the inputs will stutter/lag for about a second and then return to smooth operation. The stuttering almost looks like it is dropping frames.

No other software is operating in the background except for default OSX operations.

Has anyone else seen this problem? Any ideas to solve it?

Thanks!


Machine specs:
8 core 2.26ghz xeon
2 x Phoenix cards (4 active HDSDI inputs)
8gb ram
128gb ssd for content
Radeon 4870 output card
osx version 10.6.2

Well I am very familiar with your issue. This issue arises as a result of the difference in frame rates between your capture card and your video card. Assuming NTSC you are capturing at 29.97 fps but if your graphics card is outputting some variant of 60hz ...say 60.02hz... as you can see these two numbers dont divide into eachother. So every so often things dont line up and you see frames missing or two frames or whatever. You can lessen this by putzing with your playback rate in catalyst. (29.85. 29.87 etc etc) In my experience this has not completely fixed this issue but will change its severity and frequency. As far as I can tell the only solution is to force your graphics card to output say 59.94hz in our example so that things line up. The Dvi Parrot may be able to do this. I am looking into this. Perhaps some more people will chime in on your post. I have posted about this several times in the past. Richard has been most helpfull.

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Originally Posted by ajmaudio

Well I am very familiar with your issue. This issue arises as a result of the difference in frame rates between your capture card and your video card. Assuming NTSC you are capturing at 29.97 fps but if your graphics card is outputting some variant of 60hz ...say 60.02hz... as you can see these two numbers dont divide into eachother. So every so often things dont line up and you see frames missing or two frames or whatever. You can lessen this by putzing with your playback rate in catalyst. (29.85. 29.87 etc etc) In my experience this has not completely fixed this issue but will change its severity and frequency. As far as I can tell the only solution is to force your graphics card to output say 59.94hz in our example so that things line up. The Dvi Parrot may be able to do this. I am looking into this. Perhaps some more people will chime in on your post. I have posted about this several times in the past. Richard has been most helpfull.

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Thanks for the ideas. I will definitely try messing with the output frequency.