And how did you sleep last night? Did you spend much time awake with the machine and mask on or did you sleep soundly for the most part?
Do you remember being awake much during the night and/or do a lot of tossing and turning?
If you say you slept soundly for the post part....try turning off or at least reducing EPR and see if the central numbers reduce or not.
If you say you did a lot of tossing and turning and know you didn't sleep well then there is a good chance that a lot of those central apnea flags (the CAs) are false positive flagging...I call them SWJ sleep/wake/junk. ...Not asleep irregular breathing flags and other than pointing to poor sleep quality they don't mean much.
You have to be asleep for them to matter.
Go here and watch the videos and learn how to zoom in and spot arousal/awake breathing
http://freecpapadvice.com/sleepyhead-free-software
These machines don't know if we are asleep or awake...they only measure air flow and awake/arousal breathing is very irregular compared to asleep breathing and the machine can and will flag awake breathing with some sort of flag. It's not limited to centrals either. I get false positive OAs and hyponeas fairly often. Some nights I don't sleep so great and do a lot of tossing and turning because of back pain stuff. My AHI is almost always 75% or more SWJ stuff.
I may have to RISE but I refuse to SHINE.