Most of my videos have very occasional, randomly occurring instants of "dark lines" which snap down from the top of the monitor screen. Duration of these is about 1/10th to 1/20th second. They seem to begin at the top of the screen (viewing on a 24 inch computer monitor, or on a 20inch laptop screen) and "snap" about 2-3% of the height of the screen. They occur regardless of the bitrate or display size I render the video. They always occur at the same place, in seconds, on a single video clip - but they occur at *different* places on each video clip. Otherwise their occurance is random - there might be two of these flaws in 10 seconds, an then no more of them for the next 60 seconds, and so on. They're not a major annoyance, but they're a flaw which I would like to avoid. Can anyone tell me what they are and how to avoid them?

I'll try to attach a very low res clip, which should show the flaws at 2 seconds and 11 seconds. Please try not to be too critical of the other aspects of this clip. I'm sending it only to demonstrate the flaw mentioned above.

Thanks - Bill Hansen Bill Hansen