Digital BW, The Print

Here is one that is stumping me. I have two Epson 9000s. If I do a head 
alignment pattern using the standard control panel procedure on one 
printer it prints 12 "patterns" of seven rows. If I do the same on 
other printer it only prints 6 "patterns" of seven rows. It is not a 
clogged nozzle problem, I get good nozzle checks. Is there some hidden 
feature I need to activate to get it to print 12 "patterns" of seven 
rows?

Mark