Step 1: Gather a squad or two of Light Assaults. Step 2: Go to a tower, biolab, or anywhere where there are lots of enemies Step 3: Make whole platoon use the jetpack, so that the sound will annoy enemies, they will turn their sound off. Step 4: Kill everyone and capture territory. No need to really QQ, although SOE could have buffed the Infiltrator, they decided to increase the sound of the LA, we just have to learn and get better. Another solution would be to remove the insanely stupid OP shotguns and give more utility and features to the LA, but SOE chose the short way out of the problem.