IoHD flashes hsync playing graphics

Playing FCS2 sequence in HDV1080i60, my Io HD seems to loose hsync on certain graphic clips. I get 1 or 2 frames of horizontal displacement of part of the screen; sometimes just the chroma, sometimes luma jumps too. Camera footage plays fine. But a cartoon animation jumps all the time. So does lots of text. I can park on a frame, some jump repeatably, some don't jump at all. If I add a gaussian blur of 2 the flashing stops! Is there a hi-freq problem with sharp edges?

Aja sent me a new box, which seemed fine at first, but I still got a couple jumps. Then I did the Sept firmware update and now it jumps all the time too. Here's a 31 MB clip that flashes for me:

http://ui.media.uiowa.edu/cmpmedia/review/hd-slate-bg.mov

FCP display has no problem, and the clips play fine on another Mac with Kona KHe. Anybody else see this?

-Brian

(Mac Pro 8 core, 6 GB RAM, OS 10.5.5, Aja 6.0.1, using dedicated Mac FW800, QT 7.5.5, HD-SDI out to monitor, HDMI to TV, both flash)

The HDV codec may be part of the issue, but rendering them to ProRes and placing on a ProRes sequence still shows the problem, albeit not as bad. So in the end I still have sporadic h-shifts on graphic material, much more frequently with the latest firmware update. And they don't appear if I blur the footage.

Could you please try my clip on your equipment to confirm? Or this one:

http://ui.media.uiowa.edu/cmpmedia/review/conedshort-hdv.mov

-Brian

Thanks Jeremy. I am talking to Aja, they're puzzling thru it.

Here's the thing... I can generate the problem with a screen of white text drifting across with a simple Motion, combined with a strong colored circle underneath. Not all frames flash, but stepping single frame across the move, many will. So, lots of edges moving, combined with strong color, cause the h-shift flashes.

Until they get a fix, I can clamp the levels or blur the edges. What an odd problem.

-Brian