SO smacks lips in his sleep 😡

Each night I have to deal with a terrible involuntary habit from my boyfriend...EVERYTIME HE RESITUATES OR MOVES IN HIS SLEEP HE SMACKS HIS DAMN LIPS...maybe 10 individual smacks in a row (yes, the type of lip smacking people do when they're obnoxiously tasting food)....every few minutes...it drives me CRAZY!! It makes me so annoyed sometimes when I'm trying to sleep that I want to slap him across the face and scream "SHUT UP!!!!" I know he can't help it but jeezus it makes me livid and makes me want to sleep in another room