White horizontal lines on image when VP is clipped

WIN XP, LDD4, HP Deskjet 1220C
I realize there are tons of posts and Kbase articles on this subject; however I haven't seen anything that narrows it down to this exact problem. I've tried several of the suggestions in the posts and Kbase - changing the image res; bringing in a fresh, unrotated, unscaled image; changing the printer settings regarding memory and spooling, etc.-nothing worked. I have narrowed my problem down to viewports that are clipped. I can make a new viewport that is the same scale, etc. as my clipped viewport and the image prints beautifully. I can also print fine from model space. When I print the clipped viewport however, the white horizontal lines appear. I have been able to duplicate this time and time again, in different drawings. Problem is, I have tons and tons of exhibits already created with clipped viewports that all printed fine in LDD2. I would love to find a solution, other than remaking all my exhibits to have unclipped viewports! Anyone have any thoughts?