Digital BW, The Print

I have QuadTone  RIP installed on my Mac G4 and it is working very well 
when I print at 1440x720.  However on all 3 of my attempts to print at 
1440x1440, the printer is literally flooding the page with ink.  The 
page is almost saturated with ink except for areas that are approaching 
pure white.  I can print at all resolutions with the Epson driver 
without problems.  I double checked to make certain I had selected 
Photograph and not Line Art when making the setup selections.

Is anyone else having a similar problem? Is this a Gimp-Print or 
Ghostscript related issue.  So far all my settings have be made through 
the PS7 print preview and print screens.  This is may first experience 
with Gimp-Print and Ghostscript and I am uncertain how I  would make 
changes there even if I had to do so.

Regards,

David