So it's supposed to do that? I hadn't noticed it at first, but in the last week, it seems to have suddenly appeared? Could be just me not noticing until recently. Is it supposed to come out around the plastic tube that the longer tubing connects to?
The air that leaks out of nthe front of the mask. It's supposed to...1.) as a vent. To get rid of the nasty bi-products of resperation. 2.) if the power goes off you'll have some way to breathe until you wake up, and take off your mask.
... so that if you're prescribed 13 cm of water pressure you do in fact get delivered 13 cm of water pressure, but we'll see what the pros have to say.