We have a user who is unable to use xvidcap to capture complex videos output by a 3D graphical package (DGI EarthVIsion, if it matters). Simple tests work OK, and he can capture mouse cursor movements, moving windows, etc. But when he tries to capture a 3D surface map with animated lines moving across it, all he sees in the output video file is the first frame. If he tries to pivot the surface, xvidcap captures movement of the mouse cursor, as well as a few square blocks of pixels around where the cursor is moving. But the majority of screen remains stuck on the first frame. It looks like it's having trouble redrawing, but I can't say for sure what's going on. No error messages are produced by xvidcap, and the length of the video and the size of the file look correct.
The odd thing is that he says the last time he used xvidcap, which was a couple months ago, it worked fine, and he captured lots of video clips. He claims that nothing has changed on his machine since then, but I can't confirm that.
The machine is a 64-bit Linux machine running CentOS 5.2 (Red Hat by another name), with 8GB of RAM and 2 dual-core 3GHz Xeon CPUs. The video card is an nVidia Quaddro NVS 290.