Have the printers been sent in for service? Why I ask is that many folk are loathe to get things repaired today. They replace them.
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Our customer has issue with his two LaserJet Professional P1606dn printers. The printing is usually missing or deformed at the top of the page. My guess is that this is issue with rubber rollers but I need some advice and/or confirmation.
The most mysterious part is that the exactly same issue happened on both printers simultaneously. Below I submit links to scans of printers' self tests/device configurations and three examples of my issue.
Self tests / Device configurations:
Examples of issue: