Digital BW, The Print

Has anyone else had experience with reddish cast shadows 
when printing grayscale converted to RGB images on an Epson 
1280. I'm using basic Epson inks as I'm not quite ready to switch 
to a 3rd party multi-black solution.

I seem to be having some reasonable results in applying a 
curve that removes shadow density from the green and/or blue 
channels, but seem to experience a general loss in contrast 
which must then be retrieved with a global curve adjustment. 

Any guidance on this matter or am I fighting a losing battle until I 
switch to different inks?

Thanks