We get this questions sometime, were the picture start rolling and turns black and white.
This results from changing the setup on the receiver for the TV output format from NTSC to PAL. Also, it is a result of hitting "factory default". The receiver defaults to PAL video output instead of NTSC, thus resulting in the rolling problem.
For a quick fix, hit the "UHF" button on your remote and use the right arrow key to scroll until you see NTSC on the front panel of the receiver. Then hit OK. The TV screen should show a normal picture now.
For more information on this issue, see: http://sadoun.com/Sat/Products/BEC/Factory-default.htm