I quote directly from the breathing-article from en wikipdia - point 4 "control" (they have links to theirs sources on that page)
(smoking is by the way also a very good example of controlled breathing - both in duration and depth)Automatic breathing can be overridden to a limited extent by simple choice, or to facilitate swimming, speech, singing or other vocal training. Breathing disciplines are incorporated into meditation, certain forms of yoga such as pranayama, and the Buteyko method as a treatment for asthma and other conditions.[8] It is impossible to suppress the urge to breath to the point of hypoxia but training can increase the ability to breath-hold, for example, in February 2016, a Spanish, professional freediver broke the world record for holding the breath under water at just over 24 minutes.[9]
just to be careful - noone was saying that this can be done to the extent of suffucation.
This thread was about the AHI while awake - I and others said: during wake times the machines do score a lot of events because our breathing while awake is different to the breathing while sleeping.
you said: no (or nearly no) events while awake. (I can imagine that this is coming from your O2-"thingy".)
there is a reason it is called SLEEP-Apnea and not simply Apnea.