Yes, sonic weapons are appropriate, because all is fair in war. They do not violate human rights, any more than any other type of weapon does. They are a new and effective way of winning a war very quickly. Although all war is sad, these weapons do not in particular violate human rights.
When drone strikes kill civilians, sonic weapons can help reduce casualties. Instead of bullets, soundwaves can puncture eardrums and disrupt the enemy rather than kill them. Death tolls are less, unless a sonic weapon somehow destroys a building and it collapses. Sonic weapons can be annoying, but shouldn't violate human rights if there are just causes to use such weapons in the first place.