Technique to fix "soft" topcase buttons?
In my travels repairing A1181s, I've come across dozens of topcases with "soft" buttons -- buttons that do not "click" on the left side, and pressing on the left side does not register. This issue can often be relieved somewhat by pressing up from the underside of the button in various places, but this only works with varying degrees of success, and often I'm left with a topcase that works otherwise, but that I can't use because of this problem. I've also soaked the button in alcohol, which can "un-gunk" the situation and sometimes helps, but again it's not a universal solution.
Anyone have any other techniques to try? Unfortunately the mechanism is sealed up, so there's not an ability get in there and mess with it.