Crazy "Rolling" colors when encoding from mythtv/1080i?

Hello,

I've installed mythtv and ffmpeg (from CVS last night).  When I try to
encode from a 1080i recording (it doesn't matter what the final format
is) the result has "rolling" collors. I used nuvexport to generate the
file.  The mythtv people say its an encoding issue.  Has anyone else
ran into this issue or is there a fix/workaround?

Thanks
Marc