QTR-Quadtone RIP

Help Please,

I'm beginning to use the "Special edition" K6 inkset (from J. Cone) and QuadtoneRIP, with an 
Epson 1400, Photoshop CS3, and a Mac.

The inkset is properly installed as is the Quadtone RIP.  I've followed the manuals supplied 
with the inkset+QuadtoneRIP to properly set the print dialogue boxes (reading the text and 
following the pictures).

My problem is...  my images' highlights have 'solarized'  look about them.  Pure white is white 
but the next 2,3 tone levels down are grays.

Yes, I've done head cleanings, multiple in fact.

Running a print through without the QuadtoneRIP produces a wonderful B/W image!

Any suggestions from Special Edition ink users or others?

Mark.