const pullAudioOutputStream: PullAudioOutputStreamImpl = turn.processActivityPayload(
  activityPayload,
  (SpeechSynthesisOutputFormat as any)[this.privDialogServiceConnector.properties.getProperty(PropertyId.SpeechServiceConnection_SynthOutputFormat, undefined)]
);

public processActivityPayload(payload: ActivityPayloadResponse, audioFormat?: AudioOutputFormatImpl): PullAudioOutputStreamImpl {
    if (payload.messageDataStreamType === MessageDataStreamType.TextToSpeechAudio) {
        this.privAudioStream = AudioOutputStream.createPullStream() as PullAudioOutputStreamImpl;
        this.privAudioStream.format = (audioFormat !== undefined) ? audioFormat : AudioOutputFormatImpl.getDefaultOutputFormat();
        // tslint:disable-next-line:no-console
        // console.info("Audio start debugturn:" + this.privRequestId);
    }
    return this.privAudioStream;
}

public set format(format: AudioStreamFormat) {
    if (format === undefined || format === null) {
        this.privFormat = AudioOutputFormatImpl.getDefaultOutputFormat();
    }
    this.privFormat = format as AudioOutputFormatImpl;
}