When you say this is typical, do you mean that the flow limitations are typically clustered within a time span of about an hour, as in the night you posted?
It makes me wonder whether it's caused by some positional change, such as rolling onto your back or tucking your chin, impeding the flow of air until you move again.
Apologies all round - I think these flow restrictions may be, at least partially, artefact.
I have just done what I should have done before my original post. I have been tinkering with the 'Preferences' 'CPAP' 'Custom flagging' in Sleepyhead - setting the flow restrictions to different levels and for different durations and then looking at the resulting SH graphs.
The results make little sense, for example, setting Flow Restriction to '75% for more than 10 seconds' gives me *more* flagged events than a setting on '25% restriction for more than 10 seconds", and etc. Repeated anomalies, with different settings, that don't seem to be logical.
In SH Mark describes this custom flagging as 'an experimental method of detecting events missed by the machine'. I now think that the Resmed ASV may not be compatible with this experimental method - even though I do seem to experiencing some sort of flow restriction at the time of these flagged events - both because they arrive, most nights, in batches (so one can guess positional and/or sleep stage i.e. REM) and because they are often at the same time as my recorded 'hypopnoeas'.
So I now think this experimental 'flow restriction' flagging is not reliable enough with my machine to use as a reason for any changes in pressure settings and I have now switched it off.
Sorry to waste people's time.
All my opinions are only as an xPAP user trying to help other xPAP users.
No suggestions I may make should be taken as professional advice.
If you have medical concerns please consult a doctor
My current pressures: Auto-ASV. EPAP 10-13. PS 3-10
You conducted an experiment. Your results produced a good discussion. This was not a waste of time.