check the bolt on the lower left side of the breech. I had trouble with mine also and that fixed it. If I remember correctly is was loose. Sounds counter productive but it fixed mine
Looks like he has a Gen 2 Mrod (from his sig) that bolt is on the bottom side of the breech in that model. Breech has to come off to get to it.
one more thing to check, right on the top back of the breech (gen2) there is a screw. under this screws there is a ball barring and spring that adds pressure to the bolt. you can unscrew it to reduce pressure. I have mind very light.