My Epson WF2530 printer is only printing in colour. Any black and white documents just come out completely blank. I replaced the black cartridge recently, and the document I printed at the time came out fine. A few weeks later, and I'm getting blanks. Checking the ink levels on the ECD display the cartridge still shows as full and the printer/computer is showing no error messages when I attempt to print. I've I've done a nozzle check and head clean and neither has had any effect. Any ideas?