Paul Ramsay, you are brilliant! My partner was given one of these, and it would play but not record. So I followed your advice of January 2009, and now it works perfectly. Very many thanks. (In a nutshell, remove the power cable, take off the top (5 screws and ease the top back) then take off the front by undoing 2 side clips and three at the bottom front, then take off the black plastic top of the disk drive after undoing 4 screws, then clean the dust off the little green laser lens. Reassemble in reverse order. It is quite straightforward and only needs one #1 Philips screwdriver. Note that I could not see any dust, but it was there!)
Again, many thanks to Paul.
Ken Mackenzie, March 2009