Thanks for feedback.

I decided thebottom strap was tight and over the jaw. The next night I lowered the strap to be below the jaw. The jaw problem did not re-occur.

I am going to experiment with some different masks

I am a new CPAP user using a ComfortFull II mask. On my third night I awoke in the morning with significant soreness in my right cheek, jaw, and behind ear. Has anyone else experienced this? Any thoughts or suggestions on what to do? I plan on discussing with my home equip provider and sleep doctor ...