I have been having a problem with printing ordinary black typescript with a Canon Pixma IP3600, but only since upgrading OS from WindowsXP to Windows7 a few weeks back, and only with the PG fat Black ink.
Printing a page goes from full good black to fading out to no print at all, in the course of printing about two pages. No grid on nozzle test, but after a deep clean all is well again, lovely black printing for a page or two. Then it all happens again!
Never had anything like this before in several years. Could this be a software problem? maybe it is failing to do routine cleaning? Anyone has an idea how to solve it?