New Resmed S9 clock time vs. usage time

Machine was on for 3+ hours and claimed only 1.5 hours.

On before 4 when I started and on until right at 7.

Sleepyhead seems to be showing it was on for 2+ hours but says usage was 45 minutes.

Rescan says 1:35

AHI went from ~5.5 to 20 (but the time was so screwed up that this may be meaningless.)

Hi - not a techie like you, and this may not be relevant, but do you know that most machines reset their clocks at noon, so retrieving info after that may not be valid if e.g. one hour was recorded earlier but you slept through until the afternoon, and only see partial stats now?

Good point, and I did know about the noon change of date.

This was 4-7, same 12 hour period, 4pm-7pm.

I am having a hard time picturing what you are seeing with SleepyHead.
Could you post an image of the detailed report...turn off the AHI graph and make sure leak graph shows.
To turn off the AHI graph just go to Preferences/graphs tab.

Also, have you confirmed that the S9 itself has the correct time showing on it's clock? The clock that's in the clinical set up menu.

If leaks were large for some reason the machine might not sense any breathing and even though the machine would blow...no therapy hours would be accumulated.