Epson 9800 ghosting

[Colorblind]

Today, I printed a page to my Epson 9800 (through my ApogeeX workflow) with a dark blue background (100c 90m 0y 10k) that had some light yellowish elements on top and got some ghosting occuring, getting slightly lighter zones in the dark blue. Tried rotating the page, ghosting was less apparent, somehow moved a bit but was still there. Did everything I could think of: check heads, remade the file, remove compression, changed resolution, build a midtone tint all around the page thinking it would maybe help and so on. So far with no success. I'm out of ideas now...

[Falstaff]

When you say ghosting I think of a second series of a lighter part of the image or type. It sounds more like the dark blue background is not consistent - going from good color to lighter color but not actually a lighter copy of an image that was shifted over? If it is an actual ghost of type or an image - I have never had that issue before. I wouldn't know where to b egin with that one.
It sounds like you did most of what I would have done. Have you tried a nozzle check, check platen gap, clean head pad for the gunk, you may even need a power clean.
Is the paper you are using coated? I have found that uncoated paper will produce the varied color results you are getting.

[Colorblind]

Thank you for your answer.  Yes my paper is a nice semi-gloss paper.  I just can't figure out what's happening.  Will have someone come and do a bit of maintenance on the machine next week...

[DigitalCrapShoveler]

Any hidden effects going on? Maybe a yellow outer glow or maybe an errant overprint?

Maybe your yellow nozzle is clogged and spraying intermittent.

Have you tried to mimic the problem with another file to eliminate the original file as a potential problem?