I didn't know how to properly explain this, but when I have problems with links, if I run my fingers along the mask and let go (snap it) in the trouble areas, it will usually fix the problem.
The other thing to look for in a full face mask... if you look at the foam part of the mask, behind the mask protector, carefully look for a small split. That will cause the mask to leak as well. That's why it's important to change the mask periodically. I change mine every 4-6 weeks.
Also, my post above should specify sleepapnea, not copd.
Janet Plank (sleepapnea.sleep-disorders.net)