Solution:

In the [Main Unit: Image Quality] group on the [Adjustment Settings for Operators] menu, select 0206: [Density Difference: Across Feed].

Decreasing the value makes the area above the center denser and that below fainter.

Increasing the value makes the area above the center fainter and that below denser.

Turn off the power and the main power switch, and then turn the main power switch back on.

The setting specified in step 1 will be in effect.

Print the image. Is the problem resolved?

If unit replacement does not resolve the problem, contact your service representative.