I'm having a very similar issue with my Resmed AirCurve 10 ST bipap machine. The usage time is continually off by an hour or so, so does not correct from day to day. How can I check/set the clock/cutoff time on my Resmed AirCurve 10? How can my AHI be correct if the usage time is incorrect?

I have an AirCurve 10 ST bipap machine. For a while now it has not been showing the full usage time. For example, last night I turned on the machine at 12:45am (it has 25min ramp up) and off at 6:15am. It showed Usage at 4H 30M. I did not wake or pause/turn off the machine during the night, and ther...