DCM1957

I'm 60 years old and I've been using nose pillows since I started 6-8 years ago with CPAP. I was diagnosed with 80 AHI and they set me up with a pressure of 11. My readings each year all show good levels of AHI less than 5. What I'm experiencing is that I find on my back my soft palate relaxes sometimes too much and the air blows back from the throat/sinuses back into my mouth. Moving my soft palate "slaps" the leak shut when I'm awake.

When I'm asleep though, it appears this occurs and then I wake up with dry mouth. It only happens every so often.

So here's my question(s).

Since the CPAP pressure helps force the soft palate down so the back of the throat is sealed, do I now need to have the pressure increased to help close the palate so air doesn't escape from my sinuses/throat back into my mouth?

Everything I've read indicates that if your AHI is less than 5, your pressure is adequate. So should I raise it considering the other side effects to the higher pressure?

Finally, a chin strap doesn't seem to affect my throat being closed as it can still blow back the air... So why should I use one?