Extron Electronics DDS 100 - Manual (Page 37)

6-3 DDS 100 Troubleshooting
Banding
Description
An overall decrease in intensity, with darker bars across the screen that
begin in a light area, and bands of normal intensity that begin in a dark
area. Because most of the image is darker, the normal bands appear
brighter.
Probable cause
The image has shifted too far to one side, and has been driven into the
blanking area, causing the display to clamp its black level to the video
signal instead of to the back porch.
Possible solutions
Use the horizontal shift control to adjust the image toward the center of
the screen. See “Adjusting an image” on page 3-5.