Digital BW, The Print

I've installed the MIS continuous flow system with the VM inkset on 
my Epson 1270 printer.  The tone of the blacks is superb, but I lose 
detail in the shadow areas.  The prints come out looking muddy.  I've 
tried using Epson matte paper, and Epson watercolor paper, and used 
the PQIJ option in the print driver.  Does anyone have any ideas?  I 
would greatly appreciate any help.
Thanks,
Bob