iBook hinge "stiffness"

Coincidentally, we received two reports in the last day or so about the hinge on the new dual-USB iBooks. The problem reported is that the hinge is very stiff and makes a crackling noise when you open it. We have had exactly this symptom with our iBook. We can usually fix it temporarily by rapidly and repeatedly moving the display lid back and forth a few inches, so as to "loosen" the hinge. However, the stiffness usually returns within a few days.

We have never taken this very seriously, treating this was as a minor glitch we could live with. But one of the readers told us that Apple agreed to fix this under warranty and he was sending his iBook back to Apple. The other reader claimed the noise and stiffness were getting worse and worse and he was concerned that the hinge might ultimately break. Hmmm...maybe this is more of a concern that we had realized?

Update: Martin Moore replies: "I can confirm this is a much bigger problem than the odd isolated case. As a consultant I have seen many new dual-USB iBooks with the problem. It does seem to affect only the older models (i.e., the first batch from delivered from Apple). Worst still gradually this stiffness may lead to the casing on the front of the iBook pulling away from the screen directly above the hinge. This will need repairing by Apple to prevent more permanent damage."

Paul Jackson had this symptom, which kept getting worse, until he simply oiled the hinge. All has been fine since. WD-40 anyone?