How much does the trailer weigh and how much weight do you have on the hitch. The Dual Cam is an excellent and well proven hitch that I used on two different trailers.
Other things to check are the tire pressures, are the weights on the trailer axles pretty much equal when towing level. What are the truck tire pressures and what rating tires are on the truck?
It sounds as though you have a trailer problem. The hitch and sway control will not cure sway, but should stop sway when induced for a short time.
What is the length of the trailer...30'? My opinion is that is too much trailer to successfully tow with a 1/2 ton truck.
Ken