"By having De La Mata place her ear into an anechoic chamber, with an ultra-sensitive microphone perched in her ear canal, they were able to provide significant evidence to the contrary. “After the first recording of it, it was ‘There’s no way, this isn’t possible.’” They tried again with her breath held, and again with her tensing her ears, and again with other members of staff, but each time it became apparent that yes, the noises De La Mata hears are seemingly something physical."

I know this is basically at the end of the article, but it's not an excuse to write such a reply

“The most mind-blowing moment, not only for De La Mata but the scientists too, came when they managed to actually record the sounds that she heard in her ears…by having De La Mata place her ear into an anechoic chamber, with an ultra-sensitive microphone perched in her ear canal”