Weird Banding when printing file made with Illustrator Freeform Gradient

When I am printing a image background I made with "Freeform Gradient" in Illustrator wired squares patterns apears that is not shown on my screen.
The image background I exported to Png, then I put it into my design in Indesign and converted everything to CMYK from there. What can I do to get around this problem?

The file exportet from my computer:

A cloese-up of the print file: