what's your fuji tech said ? Laser is one of posibility, but i hope it's not the laser... is there any laser calibrating menu in Frontier ? (sorry i don't have frontier minilab, i use Noritsu)...In noritsu minilab, if you're not satisfied with your print you can always calibrate the laser with laser calibrating menu.......I ever see how frontier works (my sister have Frontier340), everytime you change magazine, frontier always feed a small amount of paper, is it (feed paper) also yellowish ? if the feed papers are yellowish (it;s sound crazy) but maybe there is a leak on exposure deck so little unwanted light enter the exposure deck.