Quad Buffer Stereo on HMD

I am using openGL to display stereo images on HMD. HMD has 1 VGA connector and no sync plug. I,

-Enabled Quad Buffer Stereo on ATIFireGL2
-Enabled 3D Support on i-glasses SVGA3D HMD
-Used glDrawBuffer(GL_BACK_RIGHT) and glDrawBuffer(GL_BACK_LEFT) to render stereo

Both opengl and i-glasses use frame sequential stereo. So, different images r shown on each hmd display. But after 5 seconds, the images swap, i.e. left image goes to right display and vice versa. The problem recurs with WildCat4.

Any ideas what the problem could be?

The problem is typical of stereo viewing devices which don’t use a stereo sync signal. In this case the graphics board left/right sequential display output is free-running, but the HMD is missing sync every so often.

Note that with graphics controllers which have hardware-based stereo display support, the alternation of left/right fields is guaranteed to occur on every VSync interval. So the problem then would be entirely with the viewing device.