On a HP 932 every 1/2" the text is lighter than the rest. I measured the distance between the lines that are lighter and they are every 1/2" almost as accurate if you would of marked them with t ruler. I looked at the print head traveling above the paper when it is printing and see there is some space (to my surprise) between the paper and the head. I thought it was a flat spot on the roller, but not the case. I changed the cartridge and the problem was less, but still there. If I use a darker setting (more ink) it isn't as noticeable, but I can still see the difference. The test page does print ok. I have cleaned the contacts, but no difference. This is the 3rd cartridge that the problem has happened on. BTW these aren't HP cartridges. I do re-fill them also. The first time I thought it was just low ink and/or dirty contacts, which I cleaned. I put a 2nd cartridge in and all was fine. I re-filled it at least once and all was fine. Then the problem returned. Any ideas?