I have the SurCode DVD pro and it can produce only 5.1 files. If you leave any of the input channels empty, it will encode digital silence in those channels.
Anyway, I've encoded a small stereo
sample in the FL and FR channels. Maybe it can be useful… The filesize is 1,5 MB.
Greetings
EDIT: Forgot to mention that it's in the DTS-WAV format