HP 3030 prints garbage

I am having a problem with my HP 3030 printer. It normally prints fine, but occasionally it will try to print one document (such as an e-mail) and will have a problem and start printing page after page of a blank sheet of paper, except for one line of garbage at the top. The line ususlly consists of sympols (hearts, diamonds, percent marks, etc.) I have reinstalled the software and tried updating the driver but it still messes up from time to time. Anyone else having this problem and how do you fix?