Digital BW, The Print

Hi group,
beeing satisfied with my LF B&W Combo (7500/MIS-FS/IP4) - 
I dedecated my 3000 printer to color work. That means after 
purging the system I installed MIS archival color inks on that 
printer hoping for some nice A2 color prints. That was yesterday, 
since then I run more nozzle checks than ever before in my life. 
The problem is: whatever I do, each nozzle check will offer 
different mistakes. Cleaning doesn´t help (even with the windex 
trick, even after letting the printer sit idle overnight). And never will 
the pattern show the same missing links. They seem to jump 
from one color to the other absolutely randomly.
What is that??
S02 from hell or just air in my carts?
Any ideas what to do?
Bernd