I have the tape silencers on the launchers
And there's your "Shlang"........

Moleskin........lots of moleskin. Beat it up and replace it as it wears.
Theres just too much surface to surface contact with that type of set up to not expect a Shlang if you are drawing and shooting against a hard silencing material.
Try the moleskin.......might change the shlang to a swoosh.