This may be old news to everyone here, but my forum search did not reveal a direct treatment of this problem.
I print mostly B&W on matte fine art papers (entrada, arches infinity) using ImagePrint and my Epson 4000 with updated firmware. No problems, fabulous prints. I print little color, and little glossy paper.
Recently, printing color on Red River Ultra Pro Satin, using RR's recommendations for driver settings (Premium Luster, etc), I have noticed horizontal banding in dark toned areas such as a night sky (dark purplish blue in the image) and a dark reddish brown dress. Head cleaning and alignment have perhaps improved, but failed to abolish, the problem. I have not noticed this printing color on matte papers.
Any further ideas? I apologize if this is well-plowed ground.
Thanks in advance,