How to select Voice-Over output speaker on IOS App

Hi !
I'm currently working on a an Iphone app for people suffering of visual impairment.

In order to get an input text, the app uses voice recognition.

The app runs pretty well with Voice-Over activated, but when the user launch the voice recognition, Voice-Over output switch to the ear speaker (and that's normal I guess).

What bothers me, is that when all the process is over, the output speaker doesn't switch back to main speaker even if I end all the processes.

For the Voice recognition I created an instance of

AVAudioEngine()

SFSpeechRecognizer()

SFSpeechAudioBufferRecognitionRequest()

SFSpeechRecognitionTask?

Then I tapped the request into the live input node and started the audioengine.

After the user finished to speak, I called

audioEngine.stop()

request.endAudio()

recognitionTask?.cancel()

Maybe I missed something when stoping everything, something about the live input node tapped :

audioEngine.inputNode.installTap(onBus: 0, bufferSize: 1024, format: recordingFormat) { buffer, _ in self.request.append(buffer)}

But I tried to

removeTap(onBus: 0)

The output speaker comes back to normal only when I close the app or going to multitasking.

I hope you could help me figure it out !

Thanks

Robin