OK - so it's not what you expected - not a whole lot we can do about that is there?
Did you try searching, either the forums (or google) to see if this was a common problem, maybe D-Link had a design error, in which case you should find many folks complaining about it, and, in fact, even you should have/would have seen the problem a looooong time ago (like when you took it out of the box).
Personally I would suggest you take a close look at the switch "actuator" - you'll find it's not actually hinged, and you'll probably find that your is broken - it is designed so that it flexes and returns to the original position without a spring - less parts, less cost - and bearing in mind that mine has worked for over six years, I'd say time proven effective.
A spot of glue might take care of your problem.