No there is no freedom to hear speech. You don’t get to tap my phone less I let you. I think you and I agree on MANY issues, but I’m not sure you have a good argument here with “freedom of speech.” Do I believe that citizens should be able to record audio and video of our public servants in action? Yep. Sounds to me like the police get to collect evidence, and we citizens get the shaft.
You're confusing two concepts.
One is that people have a right to privacy and their speech uttered within the confines of that privacy is theirs to do with what they wish.
The other, however, is that the freedom to speak implies that one can be heard. Those whom you would have hear you, have a right to hear you, without government interference.
To suggest that a policeman has an expectation of privacy when conducting his business which trumps the rights of those for whom he serves to observe that activity, is to provide him with a powerful tool of tyranny.
When you mount a soap-box to speak your mind, the government has no power to deny those who would listen the right to do so. That is part of THEIR protected freedom speech.