Digital BW, The Print

Hello,

I am just starting to use an 1200 Epson (bought at ebay) with MIX VM inkset in a
CIS. First,it worked fine, but soon I started to realize that the steps I
printed looked not completely linear. Then, I tried to print test steps for
Paul, and suddenly, I started to realize that some inks were missing. When I
print the nozzle check, yellow and Photo cyan ink is missing. Sometimes,
cleaning the nozzles help, and all nozzles are there, but soon (a few printed
lines later), these two colors fade and are away. Sometimes, cleaning does not
help, but after waiting some time without cleaning, some nozzles print again,
but fade soon. Has anybody experienced something? 

Thanks a lot,
Ernst