I started my CPAP officially about 3 months ago, but I've not been using it every night--mainly because I'm sleeping less with it on! But my resolution is to use it every night. So, I put it on the other night, and found that every time I inhaled, the mask whistled! I'm surprised my dogs didn't come to me every time I breathed in!
Next day I took it all apart and put it back together and suddenly everything is so much better! Not only did the whistling go away, but there's less noise in general, no leaks and I went right off to sleep. I'm feeling much more positive about it now.