R1800 IR CIS has red ink drops

Hi,

I have an R1800 with Ink Republic CIS; about 6 mos. old. It is leaving small red (or magenta) ink drops at random places on the print. Latest print had two drops near the left margin and one right in the middle. I took the dampers out looking for leaks but did not see anything. I dabbed the pads on the left with a paper towel (absorbed a lot of ink). Nozzle checks are good. But, the drops persist.

Any suggestions?

Thanks in advance.

Bob Schoner