QTR-Quadtone RIP

I am seeing posterization in midtones on a new 3880 using QTR.  I am using CS3 on a Mac Pro 10.5.2.  I dug around and saw similar issues but no solutions.  Is anyone else still having these issues or has anyone found a cause/resolution?
Thank you so much for any info.

Never mind .... I tested using Epson's driver for RGB and it is doing the same.  ABW works fine.  Matt prints work fine. Not sure what's wrong, but it's apparently not anything with my QTR set up.  

--- In QuadtoneRIP@yahoogroups.com, "melodi.roberts" <melodi.roberts@...> wrote:

>
> I am seeing posterization in midtones on a new 3880 using QTR.  I am using CS3 on a Mac Pro 10.5.2.  I dug around and saw similar issues but no solutions.  Is anyone else still having these issues or has anyone found a cause/resolution?
> Thank you so much for any info.
>