Quoted from Whysnow:
You own four pins? Time to bust off two nuts and add on two washers.
I think you will be just fine. Do it with the power off if that is not obvious.
This was added in production machines a long time ago when you first suggested it BTW.
The issue is most likely just a switch adjustment and a cleaning with a piece of printer paper between the contacts to remove any manufacturing oil or dust that could be on the switch. I will look at the code as well and make sure that the hits are not being dropped by the software at times.