Does the gun actually fire properly without having any bolt stick? Make sure you do have the largest carrier size that doesn't leak. Sometimes a carrier that is too tight can cause the oring to get pushed back as the bolt stem goes into the oring. This will keep the vent hole exposed and allow a leak, even though you have a small carrier size. Bolt stick is a tell tale sign for this condition though.
Have you checked the oring that goes around the outside of the carrier? They typically never leak, but if it did get a blemish, it can be a source for a leak.
Is your rail spacer installed?
I would retune the level 10, especially if you changed the oring. When the leak is present, put your finger on the tip of the bolt and gently push it back so see if it stops the leak. If it does, then your bolt is probably sitting too far forward. That could be due to wear on your sear. If the leak doesn't stop or just changes sound slightly, then your carrier size is too large.
It could be that you have a bunch of orings that are slightly out of spec and can't be adjusted down to the proper tension. If this is the case, you will need to get some new orings and get rid of the ones you have.
Except for the Automag in front, its usually the man behind the equipment that counts.