Any AAV needs access to air. Whenever an AAV is installed in a wall, it needs a grill that allows air.
That would be a good fix for your problem.
This is a good lesson for all. You can't run a fixture from the top floor and try to "trap" on the floor below.
The draining water develops so much speed, that it siphons the trap dry. Or installing a trap without a vent also will siphon. Plumbing 101
Oatey Sure-Vent Wall Box