Currently, I'm recording audio on the Apple Watch using the presentAudioRecorderController and sending it to the corresponding iPhone app.The audio format by default seems to be recorded on the Apple Watch using two channels and there doesn't seem to be a way to change that.For various reasons, I need the audio format to be only one channel. I was hoping there would be something on iOS to convert the audio file from stereo (two channels) to mono (one channel)Right now, I'm investigating if this is possible using AVAudioEngine and other various related classes. I'm not sure if it's possible and it seems very complicated at the moment.

In my iOS app, I am trying to transcribe prerecorded audio using iOS 10's latest feature, the Speech API.Multiple sources including the documentation have stated that the audio duration limit for the Speech API (more specifically SFSpeechRecognizer) is 1 minute.In my code, I have found that any audio files with a length of about 15 seconds or more, will get the following error:Error Domain=kAFAssistantErrorDomain Code=203 "SessionId=com.siri.cortex.ace.speech.session.event.SpeechSessionId@50a8e246, Message=Timeout waiting for command after 30000 ms" UserInfo={NSLocalizedDescription=SessionId=com.siri.cortex.ace.speech.session.event.SpeechSessionId@50a8e246, Message=Timeout waiting for command after 30000 ms, NSUnderlyingError=0x170248c40 {Error Domain=SiriSpeechErrorDomain Code=100 "(null)"}}I have searched all over the internet and have set to find a solution to this. There also have been people with the same problem. Some people suspect that it's a problem with Nuance.It is also worth noting that I do get partial results from the transcription process.Here's the code from my iOS app.` // Create a speech recognizer request object. let srRequest = SFSpeechURLRecognitionRequest(url: location) srRequest.shouldReportPartialResults = false sr?.recognitionTask(with: srRequest) { (result, error) in if let error = error { // Something wrong happened print(error.localizedDescription) } else { if let result = result { print(4) print(result.bestTranscription.formattedString) if result.isFinal { print(5) transcript = result.bestTranscription.formattedString print(result.bestTranscription.formattedString) // Store the transcript into the database. print("\nSiri-Transcript: " + transcript!) // Store the audio transcript into Firebase Realtime Database self.firebaseRef = FIRDatabase.database().reference() let ud = UserDefaults.standard if let uid = ud.string(forKey: "uid") { print("Storing the transcript into the database.") let path = "users" + "/" + uid + "/" + "siri_transcripts" + "/" + date_recorded + "/" + filename.components(separatedBy: ".")[0] print("transcript database path: \(path)") self.firebaseRef.child(path).setValue(transcript) } } } } }`Thank you for your help.