aye, that sounds like what the problem most likely is. I found a couple of sites you might want to try:
HERE if it might just be a dirtied lens
HERE to adjust the laser itself, although you need an oscillioscope, and I don't know how many people have one of those lying around.
HERE also has a ZIP you can download with very detailed instructions on laser adjustment, although I just glancd through it.
I hope one of those helps! :bye: