See my notes on the image. It's not the CA-OA detection ripple.
My best guess is low-level vibratory face-mask leak (think face-flatulence)
Any other theories?
PS. If it IS face-flatulence then that would be hilarious for people obsessing about RERA-like waveforms.
OSCAR uploads - Organize Charts - Removing Calendar and Pie Charts etc to show the Settings
OSCAR uploads - Attaching Charts to your post
OSCAR help pages
How to obtain your Clinician's manual: Click me and go to "Section Three" on this page
Data Interpretation
Treatment-Emergent Central Apnea
Machine Choices - Good and Bad
Download Polyman (EDF Viewer)
Which ResMed machines support which modes (scroll to final post)