[theora] choppy motion/rectangles

[Evuraan]

Greetings.!

In rapid action frames, I see lots of small rectangles which many
together render a choppy sense of motion. I've attached screenshots in
attempts to convey what I mean:

http://24.16.26.121/screenshots/images/1253914810.jpg
http://24.16.26.121/screenshots/images/1253914788.jpg


I understand the lack of h/w acceleration and such, but I feel this
can go away. If I am at all correct, what attribute of the video
should I tweak so that this goes away, or atleast becomes bearable?

 I tried some tweaks, and I am continuing to, but some of you might
have already been there and done that, hence the question.

many thanks in advance.!