What should I ask my sleep doctor?

I'm going for visit to my sleep doctor tomorrow. This will be the first time I see the doctor since starting CPAP. I've tried three different masks, a nasal mask plus two different nasal pillow masks, and still am not able to sleep through the night and although my AHI is usually than 1.0, I definitely want to bring that up with the doctor.

What other questions are good to ask the doctor on a post CPAP usage visit?

Dave.