EM flipper "buzzing"

Cleaning up my games in advance of hosting league and noticed that some of my EM’s are completely silent when the flippers are engaged. Other games you get varying degrees of buzzing/chattering. Sometimes it’s even the same flipper on the same game - hold the flipper up and no noise, do it again and you get some chattering.

Curious about the science behind that … And of course if there’s a sure fire way to get rid of any of that chatter.


Depends on the game…

Easy fixes
Coils that are loose in the flipper plate - adjust the brackets
Coils that are loose in the flipper plate and need the spring washer to hold them tight
Plunger and coil stop chatter - can be from worn or incorrect coil stops (DC vs AC stops)