[QAPereo]

Yes, microwave energy can do pretty much exactly what you're saying, and perhaps other forms of radiation could directly activate nerves as well. It's also possible that if the brain damage includes auditory processing then it could be phantom sounds. It's too many options, too little evidence, but microwaves seem like a good culprit. It doesn't seem too far-fetched that such a system could induce something like a "recording" as well, or that recording could be coincidental.

If they had devices in the embassy which required maybe intersecting "beams" of microwaves to power up and transmit, and something went wrong...