more on my early morning awakening

[eekamouse]

        Hi guys,
I'm back seeking your collective wisdom. As I've said before, my biggest problem is that I'm waking up super early, often with the feeling that the machine is suddenly pushing an uncomfortable amount of my air into my face, so much so that it rushes out of the mask. After feedback from you guys on previous occasions, I got myself a neck brace thing to lessen positional apnea. I wore it last night and I feel the jury is still out. It wasn't particularly uncomfortable but I'm not sure whether I slept better. 
Anyway, I woke up some time after 3 am and while I was lying there I felt the machine start ramping up the pressure. Because I was awake, I have no idea what triggered it -- it was like someone just turned up the volume. When I look at the chart, I can see the moment on the graph.
So my question: why is it doing this? Is it performing some necessary function that I don't understand or is there something wrong with it? And what strategies should I adopt?
Thanks in advance!
Jeff