Comment 4 for bug 288816

I also have this problem. And, the myth devs have locked down the bug report because it is magically fixed in 0.22, something to do with ffmpeg. I am still hoping to see a workaround for 0.21-fixes.

For me, it happens both with ffmpeg+xvideo and a vdpau+vdpau profile (using the backported patched mythbuntu packages). Since you say it is related to ffmpeg, can it be worked around by using a non ffmpeg profile?