I edited this post so it could be more straight forward.
I wanted to post this because I saw a several people having a tough time getting their tuning right. If you are chasing the needles with seemingly no end in sight this should be your starting spot.
Take the whole fuel system off ie; tank, header tank, filter and all the tubing. Get a bucket and fill it half full with water. Get a air pump like a basketball pump. Now assemble all your components the way they would be on your heli. Plug the end of your post filter hose Put the pump needle in the muffler pressure line and pump 2-4 times. Now plug it and hold it under the water see if it holds pressure and look for air bubbles. If no leaks put it all back on and fly. If it leaks fix the bad parts then Fly!