When I inhale, I feel air escape from the valves around the air inlet of the mask where the pivot join attaches. When I exhale, no air escapes from the mask. Instead, all my exhaled air goes back up into the tube. Then when I inhale, it drives my previous exhalation back into my lungs. Shouldn't it ...

I find this extremely annoying too. My humidifier heats the air. I need it cold or my head gets extremely uncomfortable and I wake up feeling like I'm suffocating. I also feel like not enough exhalation clears from the mask, like I'm breathing into a bag. I basically can't use it.