I would run through all of the maintenance settings. Head nozzle check, head cleaning (deep, uses the most ink), I'm using a Pro-2000, 2100, and 6100, so my settings may be a little bit different.
It also maybe the paper size configuration. That may not be the right word for it. There is a tool which allows you to print a sheet and measure with a ruler to see if the printer is physically printing at the correct scale. It looks like the size of the print head is where you're getting a hairline of overlap and perhaps the machine is thinking it is moving the paper exactly the length of your print head, but it needs that value reset.
