[Ratters]

It looks like everyone's solution to this problem is the correct solution. Which ultimately means you should do a complete gearbox service. Shimming, aoe mod, trigger plate inspection or replacement, trigger contact points and re-grease of the mechanical contact points. Try a small amount (a skinning) of dielectric grease on the electrical contact points. It might help reduce carbon spots from arcing and also guarantee a better electrical contact. Also, as was said make fully committed trigger pulls this will reduce short cycling the gearbox.

The best gearbox you can build is built with the desire for excellence in its mechanical function.