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We are experiencing print quality deterioration with our Xerox 7800. The prints are full of horizontal and vertical lines, they look almost as if there is a line screen on the image. We have ran paper calibrations as well as color calibrations. While calibrating the grey balance, there isn't an option that is actually a neutral grey. This is evident in all three shades, but especially in the dark calibration. This seems like some sort of ink contamination issue. We only use OEM cartridges. Further, the color the printer yeilds is very innacurate / muddy. This occurs with both the printer managing colors and with photoshop managing colors using profiles we created and sucessfully used in the past.
Any ideas are appreciated.
Using Mac OSX 10.12.5; Photoshop CC 2015