I have slept with a CPAP machine for about 22 years now. Until recently it has worked fine. For whatever reason the same solution no longer solved the problem and I've been in various levels of sleep deprivation for months now. I remarked on this problem a few weeks back and texasts helped me decide to go another route, that of a full face mask. The original masks were less than satisfactory but they have reinvented them (I love being on the back end of the baby boomers) so they are comfortable and work with my beard.
The upshot is I've had several days of excellent sleep. I'm not fully used to the mask but my machine measures all kinds of elements of sleep and it says I'm getting nearly a perfect, apnea free, sleep. I can feel the difference throughout the day.
After a lot of years on ships where there is no such thing as a full night's sleep I treasure my sleep and increasing the quality makes such a difference to my waking attitude.
Time to start my day job. Second to last day. Only two and a half hours today. A couple of hours tomorrow and I'm on my own again.