I have an EPSON WF-2540 that is not printing correctly. I do know that it does need ink. But black is not low but is getting there. Yellow and Cyan are low. I thought I could print with just black ink only, but whenever I click print (b&w only) nothing is showing up on the paper. Would this be a sign that I need new ink or that the heads are clogged?\n\nHelp please!