I've seen this exact same thing on the 9600 with StudioPrint Smooth Diffusion dither with color ink only (not Quads) when I'm lining an environment. The way I got around it was the same as John Vitollo's. It's a resolution thing.
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Re: [QuadtoneRIP] Re: QTR-2200 printing faint vertical bands
2006-11-10 by Walker Blackwell