Printouts from my HP 4si come out with shadows on the page. For example if I printed a page that said TEST I would see the word appear again lower on the page only lighter. According to the ruler I have in my manual the shadows are 3 11/16 inches apart which means the photosensitive drum on the toner cartridge is causing the problem, but when I put the same toner cartridge in another printer I did not have that problem. Does anyone have any suggestions as to what might be wrong? Thanks.