Mask leak alert?

The Remstar has something called "Mask leak alert". For the life of me I can't figure out what that would mean.

Believe me, when my mask leaks (which it does often, I have the Respironics ComfortFull FF mask), I know it and I sure don't need an "extra" alert to let me know. What happens, do you get some extra sounds beyond the usual whistles or air rushing into your face? Wow, just what I need, another alert.

Can anyone explain what that means.

Snorenomore, who never experienced such strange sounds until he slapped on the mask!

If you get a very large leak or the mask comes off, the unit will beep. You can test this by turning it on without the mask on your face...