You need a spring, i had exactly the same problem on mine
Alias with cp roller bearing trigger. You can use the small spring out of a pen, adjust the centre grub screw so that it is just touching the contact on the micro switch. Then adjust the top grub screw(spring tension) clockwise to greaten the pressure on the spring, this will help it (told this by a timmy tech)and then adjust debounce and mbounce accordingly, my settings are deboune 9, mbounce 5 with a frenzy board.
james