Your question is a little vague, but here are a few suggestions ....Ruling out the camera ....
Could be a few things I suppose. Are you the only one who prints out on the printer? could someone have inadvertently changed the options??? that might be something to look at. have you mistakenly installed a different brand of ink???? I take it that after 2 years you have definitley changed the ink tank....
Could you describe what the drop in quality looks like? 2 years ago 1.5 mp was good but it has now been surpassed with over 6mp. Have you changed software?
Let me know some more and I will try some more.