Pushing the air nozzle wont do anything. It should be on a spring system thats operated by the motion of the gears, and will return to any position it wants to even after being "pushed".
The problem you're describing has happened to me before. It stemmed from 3 things, magazine well, magazine, and hop up. The mag well was plastic, and too loose around the magazine, so the magazine wouldn't seat properly against the bottom of the feed tube. I was using crappy hi cap mags, enough said. My hop up had a very weak bucking, it was too easy to push bb's through the chamber. My solution? Classic Army.
If you LOVE your TSD, look into a stiffer bucking, different mags, and the integrity of your mag well. Otherwise, reconsider your weapon choice. When I say that, I don't mean to sound like an ass, if I do, I apologize, but money saved while buying an AEG will never compensate for the loss of quality.
