An Adjustable gas tube may be the answer.

Slowly open up the barrel gas port until you hit the ideal speed wanted with the AAC flash hider (gas tube wide open), then you will use the adjustable gas tube to back down the gas pulse to cycle the ideal speed wanted when the other back pressuring type units are installed (to hit the ideal speed with them as well).

P.S. The canned rate is about the speed that I like the shorty’s. Allows me to quick burst, and move rapidly. But if you’re dumping, you’re going to go dry like quick.