If we're going to speculate, one could speculate that it was an anti-spying device which inadvertently caused these issues. If you want privacy you can either

If we're going to speculate, one could speculate that it was an anti-spying device which inadvertently caused these issues. If you want privacy you can either try to build isolated structures or rooms, or you can try to overwhelm the listener with noise. The US has employed both techniques previously. What if they were trialing a new defensive (anti-spying) technology that went wrong? The US government has certainly gone strangely quiet on this incident.