I do not understand why it happens, but sometimes (only sometimes) my dots out of Vibroplex Blue Racer become very unstable. Apart from the initial chatter when the contact closes, there is somewhat delayed bounce of the contact (red), which is observable by listening to the side tone (yellow). See the third and the fourth dots. I have not checked the RF signal yet, but I presume there is also some annoying effect, too.
To avoid any loose contact at the pivot, I am using a jumper to directly connect the lever to the ground, but it does not improve the situation.
Another example. This time see the 1st through the 3rd dots.