Why do people buy Lexmark? I have had nothing but incredibly bad luck with that stuff.
OK let's cut to the problem.
I have a Epson Workforce 845. When mine did that I solved the issue by changing the printer set up to buffer all the documents before starting to print. If the set up is set to send directly to the printer, it prints as fast as the data comes across. One line pause one line pause.
Be sure you have the latest drivers and go through the set up with a fine toothed comb.