I've full inventory - no available slots.
I find food, and i right click "eat" so that food comes to my hands.
After i'm done eating, i have that "waiting" message when right clicking items (i dont know the english translation, in my italian version message is "ricezione in corso") and desync value goes up.
This happened 2 times out of 2. First time i logged out to solve, second time i equipped a weapon - that made food drop from my hands, and things went fine again.
I'm *not* sure this is actually a bug rather than a big coincidence.