Validity of Acoustic Weapon Effects on Biological Organisms?
There are a few things which can lead to miscommunication regarding the potency of acoustic weapons, but there are two main things to consider: source levels and duration.
Most organisms can tolerate loud sounds, within reason, for a short period of time. However, no matter how short, at certain levels acoustic weapons can cause temporary or permanent hearing loss, nausia, gagging, and disorientation.  Weapons with a lower source level played over a longer duration will be easier for organisms to initially ignore, but exposure to weaponized source levels over time will lead to internal issues with health, including a decrease in fecundity and nutrient digestion.
Often military and sometimes scientific reports will focus on one particular type of weapon used for a specific purpose, and deem its use acceptable or not. Many scientific studies take more factors or variations into consideration.
Ultimately, its risky because we don't have enough data about the long-term effects acoustic weapons can have on a population, and they also don't appear to be particularly effective when it comes to humans. The Acoustic Weapons (chapter 7) in 'Non-Lethal' Weapons1 by Neil Davison sums it up nicely.
Reference:
1: Davison, N. (2009). 'Non-Lethal' Weapons. Springer.