Stuttering in animated programs

[tinycorkscrew]

I'm in the second day of a trial of Sage MC 6.1.9.

I'm using Purevideo as the MPEG decoder. Sage is set up for defaults except for VMR9, 3D acceleration, and full screen exclusive.

My tuner is an HD Homerun.

Most HD programs look great. I have to change Purevideo to "Film" mode instead of "Smart" on CBS to get rid of some stuttering. CBS recordings don't require the switch to play properly in WMP.

Animated programs, though, are a mess. The Simpsons, Family Guy, and Caillou all stutter incessantly no matter what Purevideo settings I use. Those programs all play fine in WMP with no issues.

When I run in debug mode, I notice that Sage is using its own splitter instead of using the Nvidia transport demux. Is there any way I can force use of the Nvidia demux?

Sage and Purevideo are the only programs installed on a fresh install of Windows XP SP2.

The computer is a Athlon XP 2800+ with 1gb of RAM on a DFI LAN Party mb.