I have been using the Airsense 10 with Full Face Mask since I was diagnosed with Severe OSA in November 2015. I've had next to no trouble until recently.
Mask Whistling started about 3 weeks ago. After doing a bit of googling, it seemed to be related to the Humidifier Settings. I decreased the setting to 2 and the problems stopped. It started again night before last. I just turned the humidifier off - I would rather have a dry mouth than whistling all night. It hasn't done a thing.
It seems to take about 10 - 15 minutes before whistling starts again, and I wake up with a wet mask. When I uncliped the tubing from the mask there is also drops of water coming from the end of the tubing. I wipe it out, but it just comes back again after another 10-15 minutes, and I haven't gotten back to sleep yet.
TL,DR - Wet Mask, Water droplets from end of tubing, Humidifier turned off, Temp set at 25 degrees (Celsius). No sleep for 2 nights - HELP!!!