Hi @Joaovictor,
I'm sorry to hear this. 
When you say that your microphone has crashed do you mean you get a error message saying your microphone has crashed or has it simply stopped working?
You can test your microphone in the built in diagnostics tool, to do so, go to: Settings > About phone > Diagnostics > Test > Microphone. How does the microphone behave in this test?
I would also recommend that you reboot your device to safe mode to see if this behavior is caused by one of your downloaded apps as these will be temporarily disabled in this mode.
Let me know how it goes. 
