Fwiw.
We already know the assembly of the rifle was sub-par. I'm going to put more weight on that than anything.
The external features seen in the pics (UBR w/ MonoPod, APEX handguard, LaRue BUIS, Surefire brake, Vortex glass w/ LaRue mount, Norgon button) are all top notch products. If the external quality is any reflection of the internal parts, I'm leaning even more to assembly error.
There could be a spring or pin out of whack... but it could just as easily be a misaligned gas block or similar. If you aren't savvy on the building of these rifles, I'm afraid a trip to your local gunsmith might be in order.
I'm still disappointed that it appears to not have been test fired. I would never release a rifle until I had flawlessly put at least a half magazine of mil-surp through it.