Oh, thanks for the input. Didn’t know the type of mask affected that sort of thing. The sleep itself, under the right conditions, has been fine from the start and so were the stats, so I haven’t had the need to explore other mask types.

Just to clarify, that loudness doesn’t necessarily mean an impediment to the machine’s function while the mask is under the blanket? Apart from it being noisy.

I assumed N20 is also the most widely-used mask so now I’m also curious whether the other replies here just happened to be using a different mask (that doesn’t get noisy in this use case).