mythtv is regularly tearing of image during playback. I started mythfrontend with "-v playback" and saw these errors:

nVidiaVideoSync: VBlank ioctl did not work, unimplemented in this driver?
DRMVideoSync: Could not open device /dev/dri/card0, No such file or directory

I've got a new Nvidia 8600GS video card...so it should have plenty of horsepower. I'm running the latest nVidia drivers (ver 100.14.11) so the feature should be supported.

Anyone know how to turn on this Vblank using the nvidia driver? Solutions?