I turn my as high as it will go every night, which is still not nearly high enough in the winter, with gas heat running. I wake up with sandpaper tongue and all, even on max settting. Very frustrating. I think I was overcharged for a really crappy machine. I should have researched machines before buying, but I was in a panic once I got the diagnosis.
Jenny, If you are using a nasal mask, the problem is likely not the machine or humidifier. It could be mouthbreathing causing pressure loss and excess air flow. What type of mask are you using? Full face or nasal only?