[Twin#1[Op-for]]

Hey guys, with my new AK it has the Mark III mosfet, the one with the 3 round burst, and all those fancy features. I wasn't interested in these, more-so just for the contact protection, but this is how it came. The thing is, when I set it up for the normal setting, IE after the starting buzzes, 5 semi shots and a burst of full auto, when I go back into semi it buzzes in between shots every time. This is not only a little annoying but stops me from using my high response, as the buzzing seems to inhibit firing. Has anyone heard of or had this problem? I've tried looking everywhere for information on this, including the mosfet instruction manual etc, but haven't found anything.

Could anyone give me some insight on what could be the problem?