Thanks, it's hard to tell whether there is a difference or not. I find the mask is somewhat noisier when it's connected straight to the cpap for some reason. Maybe the moist air makes a difference in the noise level, I don't know. I guess I'll ask the doctor next visit and hope he doesn't say go for...

Thanks - I've checked for leaks, but don't think there are any. It hooks by a short hose from the cpap to the humidifier , and the longer hose that connects to the mask hooks to the humidifier instead of the cpap . The air has a longer way to travel from the cpap through the humidifier , but I don't...