Why don't you rent a flat beside your Airbnb and see what your neighbours are complaining about, not knowing from one week to the next whether one is going to get a nights sleep is a killer because of noisy inconsiderate guest next store, particularly when your Airbnb guest couldn't give a tosh.
You need to do more than mention noise issues in the leaflet you leave in the apartment. Nowhere in your listing is this mentioned. I would rewrite your listing description, making it clear that this apartment is for quiet guests only. Also make that clear to guests in a message when they book. If guests ignore that, and continue to disturb your neighbors, you may want to consider only renting to 2 guests at a time, rather than 4.
@Suzan932 you could also install decibel-monitoring devices such as NoiseAware -- be sure to disclose in your listing under "Things guests should know -> Safety Devices" -- so you are aware of any issues before your neighbors complain.