Have you changed these options at all?
I would also suggest changing Color Correction to None.
Maybe somebody will correct me, but I'm pretty sure this is how solid-ink printers work with color, they dither color, without dithering they don't function.
The only "pure" colors they can do are when printing pure cyan, yellow or magenta, since no mixing needs to take place, as shown on test prinout for each color.
You can only migate it by selecting highest print quality, but here will always be dithering, because it's simply the basis of how solid ink functions.
I can see, photographs not looking good, but personally I like the look and brightness of typical business graphics and such.
I have a ColorQube 8580 printer that is great for printing text but is all but useless for printing anyone else despite its solid ink technology being ideal for printing business ands professional documents with colour images.
I have tried printing regular tiff, jpeg, gif, pdf, and even PowerPoint files with everything from photographs to simple single-colour blocks but no matter what I do everything comes out looking like total crap because the printer is dithering all of the colours rather than just printing the colours themselves.
I have even gone in and created pure-colour vector files with clearly separated single-colour graphics to test things out with the outcome being the same 1990's era print quality. The same has held true for sending such as ideal as possible documents directly to the printer as postscript with no software intervening.
Right now, I need my printer and am stuck because it's entirely worthless to me unless I can turn off this insane function. There does not appear to be a menu entry on the printer, and none of the options Windows I can pull up in any programme (Mac OSX, iOS 9, MS Office, Gimp, Preview, Safari, Firefox, etcetera) has an option dealing with dithering as far as I can tell.
What good is buying an $800 CMYK printer that uses $600 ink if you can't actually print individual colours?
Here are images. The first two are of the printer's own test pages showing that it can in fact print sharp crisp pure-colour images when using files stored within its own system:
Yet here is what it produces no matter how you send it to the printer:
And just to compare, here is the original version of that Pantone page which shows the file being printed does not look anything like the mess the printer's producing:
I hope someone can help me out on this. I've seen through searching that I am far from the first person to ask about this very same issue but instead of posting answers, support staff on all of those other threads have just posted a response asking the original poster to contact customer support by phone.
Thanks in advance.