I am having some problems with my TM M4. It seems to fire most of the time, but dry fires (no bb comes out) often enough. I have stripped the gun down and really took a good look at it. I have done this a couple times before and know my way around. What seems to be happening is the air nozzle does not always reset itself all the way back to the correct starting position. It ends up blocking the feed for one or two trigger pulls, then resets itself properly again. I know this because i shine a flashlight up the feed and watch it happen when i dry fire the gun. This action happens in semi and full selections. What would be causing this, and how do I fix it? Any help would be greatly appreciated. Thanks in advance..