sfspeechrecognizer

I am implementing Speech Recognition in my app. When I first present the view controller with the speech recognition logic, everything works fine. However, when I try present the view controller again, I get the following crash: ERROR: [0x190bf000] >avae> AVAudioNode.mm:568: CreateRecordingTap: required condition is false: IsFormatSampleRateAndChannelCountValid(format) *** Terminating app due to uncaught exception 'com.apple.coreaudio.avfaudio', reason: 'required condition is false: IsFormatSampleRateAndChannelCountValid(format)' Here is the code used for starting and stopping recording:

I am hacking a little project using iOS 10 built-in speech recognition. I have working results using device's microphone, my speech is recognized very accurately. My problem is that recognition task callback is called for every available partial transcription, and I want it to detect person stopped talking and call the callback with isFinal property set to true. It is not happening - app is listening indefinitely. Is SFSpeechRecognizer ever capable of detecting end of sentence? Here's my code - it is based on example found on the Internets, it is mostly a boilerplate needed to recognize from