DLPC350: Missed frames when streaming to DMD via HDMI

Hi,

We are trying to drive the DLP4500 DMD through the HDMI port using the DLPC350.  We can successfully stream to the DMD, however every so often some frames seem to be "missed":

If we send a sequence of black and white frames through the HDMI to the DMD, then image the DMD using a camera that is triggered from the TRIG_OUT_1 pin of the DLPC350, we expect to see alternating black and white images on the camera.

Instead, we occasionally see several black images back to back, or several white images back to back, implying that some frames were skipped (never got to the DMD).

The camera can give out a trigger whenever it captures a frame.  The number of triggers from the camera always matches the number of triggers from the DMD, so it is not that the camera is missing triggers.

We are drawing images onto the DMD screen in windows using OpenGL in a very lightweight program.

Experimentation strongly suggests that the problem is that the HDMI frames sent to the DMD are sometimes incorrect (i.e. sometimes the PC sends the same frame twice).

Is this an issue that you have come across and do you know any way to solve it?  Essentially we need to make sure that the DMD display is always in sync with the display on the screen.

Thanks.