SDK 32.6.1 Release I have three HDMI outputs How to force one of the HDMI output formats to be yuv422 ??

I think you misunderstood the kernel. 08_video_dec_drm is just a userspace code, it asks the kernel to output the YUV format, and kernel can do that. It means the kernel supports YUV format. The real things that do not support YUV mode is the Xorg driver. Which means the Ubuntu GUI you see does …