Mitsubishi VS-50803 Owner's Manual page 62

Using video mute
Vvqaen Video Mute is ON, yoar TV will display a blue or gray screen whenever
i_ receives a weak signal (or no signal at all) from Inpa_-l, Input-2, Input-3,
DVD or Input4. Ifa PIP is displayed _he screen will be gray. If no PIP is
displayed, _he screen will be blue.
When Video Mute is OFF, _he screen will be black whenever it receives a
weak signal (or no signal at all) from Inpa_-l, Inpa_-2, Inputs3, DVD or
Input4.
60 Chapter 2: Operating Your TV