First ammendment right to invade privacy and broadcast what someone says in private to the world? Yeah.....right....
Invade privacy? If the person is repeating what is said to them, they have not "invaded privacy". Betrayed a trust, maybe--but you cannot lock up (or pillage the belongings of) anyone who betrays a trust.
As soon as you start distinguishing between "acceptable" speech and "not covered" speech, you have already tossed out the 1st amendment--the only question left is how strict a censor you are.