How to detect when the user is talking and is not the speaker being loud in VoIP/RTC examples

[migmel]

Hello guys,
I am trying to solve an echo problem happening when the speaker is very loud and the AEC does not completely remove the echo.
For this purpose i need to know:
1. How to detect when the user is talking and the microphone input is not actually coming from the speaker.
2. How to detect when the speaker is playing the far end user conversation. In other words, how to automatically reduce the microphone sensitivity whenever sound is coming out of the speaker?
What i want to do is reduce the microphone sensitivity or turn it off when the speaker is very loud and detect when the user is actually talking to restore the microphone sensitivity.
Is it possible to do ?