Epson WF-2540 leaves hickeys

This Epson WF-2540 has all of a sudden started leaving ink blotches/hickeys on the leading edge of paper and especially bad on envelopes.

I have done all the maintenance procedures more than once to try to get rid of this problem to no avail. I have also scoured the internet for several hours using several search terms and several different search engines without finding anything about this particular issue. As many know, the Epson website is basically useless and since this is an older machine it is no longer "supported". (Planned obsolescence don't-cha-know?)

Any help leading to a resolution of this problem will be greatly appreciated.