[tiimbz]

There is also a theory by this audio engineer that the sound is caused by the flag poles opposite the embassy building, which can start shaking with the right amount of wind, which could cause a sound with an infrasonic resonance frequency.

Link: https://eelcogrimm.tumblr.com/post/181905499356/cuban-duck

[ricardobeat]

That sounds like the same kind of fantasy as shown in this article. The incidents happened at their diplomatic homes and hotels, not the embassy.