Thanks HB.
Try this one. RTR on Hot Bird (11034V 27500 3/4) - will have PLANETA RTR logo at the top. If you could try cycling through various options in A/V settings, that would be great.
For example, the "display 4:3 content as" option "pillarbox" will show original 4:3 aspect with black bars on the side. "Just scale" will stretch it to fill the screen but losing the aspect ratio, "non-linear" seems to be the same as "just scale" and "pan&scan" should zoom into a picture, filling the screen and keeping the aspect ratio.
These options don't appear to do anything in Zeus... but 16:9 ones allow you to either zoom or display original 4:3 aspect. This leads me to believe that Zeus recognises 4:3 video as 16:9.