Bi-pap pressure drops

I would be just guessing what is going on without an OSCAR chart. Here is OSCAR chart of an APAP machine which is in Auto. This is an example from my wife's machine. Notice how the pressure goes down at 3:45 or so in the morning, and then she wakes up. There is a break and then the machine starts again.

Another quick check you could make is to see what your minimum pressure is set at. If it is too low you can get the effect you describe. Out of the box the machine is typically set for a 4 cm minimum pressure, which for most people is too low, to the point of feeling suffocating. I normally suggest a minimum of 7 cm, unless there is some reason to go lower. I set my minimum at 9 cm and that feels comfortable for me during the going to sleep period of time.

That is very strange. To be clear are you talking about the period of time from 21:09 to 21:12? - This would seem like the mask was not on, but I am not sure. Don't know how else there could be no flow?

Or, the time starting just before 21:22? - Here there seems to be flow, but the IPAP pressure has dropped to 11 cm suddenly.

I am less familiar with the AirCurve machines, but my first thoughts are that the machine may be defective.

You could try this link for a Clinical Guide. As I say, I am not that familiar with the AirCurve 10 VAuto. Perhaps you could review the setup portion of the manual to see if there is anything amiss. But, I'm thinking it is perhaps defective. I recall they have a 2 or 3 year warranty?

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