Increased AHI w/ Liberty

Why would my AHI be going up while using the Liberty? Is it due to the mouth breathing? I notice that whenever I use the chinstrap my AHI goes up too, weird huh? And with the Liberty I've been using my chinstrap because of a dry throat (on the suggestion of others). I'm at almost 8 right now for the 7 day period and it keeps going up everyday. Why? I'm trying my darnedest to get this to work out, this whole CPAP thing and really do want it to work but I'm going on two months now of trying and it's getting kind of frustrating!! Thanks for any input!!

~Heather