(you can see a thread about the issues here, "Persistent sleeping position pain", mostly related to having my neck twisted too much):
viewtopic.php?f=1&t=106956
But the problem is that I have lots of mouth leaks. I actually got the sad face on my machine one day, and we all know how hard that is!

I have tried several different chin straps (don't work and give me a headache), some extremely sticky tape (still came loose) and even an ACE bandage wrapped around to form a chin strap. Even if the strap keeps my teeth together, the air still leaks out the sides.
I tried the FF mask again last night, and it was just as unworkable, with big leaks, aerophagia, and my front teeth aching from being pushed on all night (and I can tell they're starting to be pushed in).
Pressure is not that high, minimum of 8, and the 95% pressure was only a little over 9. But using the FF mask with my neck twisted, it goes up to 13 or 14. But the leaks keep partly waking me up enough to stop them by closing my mouth or whatever, as you can see from the oscillations in the graph, and this is having the same effect that the apnea has. I am mentally wrecked, very tired, and can hardly remember anything.
I'm usually quite inventive but this is taking a toll on me mentally so that I can't even come up with good ideas. I'm desperate to just get a good night's sleep!