There's also the issue that the device won't respond back at the sub-audible frequency.
The Crown prosecutor of Russia met with his father Aras this morning and in their meeting offered to provide the Trump campaign with some official documents and information that would incriminate Hillary and her dealings with Russia and would be very useful to your father. This is obviously very high level and sensitive information but is part of Russia and its government's support for Mr. Trump - helped along by Aras and Emin.
Saliva causes cancer, but only if swallowed in small amounts over a long period of time. -- George Carlin