private void Start()
    {
        if (Application.isEditor)
        {
            return;
        }

        if (Delegate == null)
        {
            throw new UnityException("[ERROR] Must set AirVRClient.Delegate.");
        }
        AirVRClientLicenseFile licenseFile = new AirVRClientLicenseFile("client.license");
        int result = onairvr_Init(licenseFile.path, AudioSettings.outputSampleRate, _profile.hasInput);

        if (result < 0 && result != -4)
        {
            Delegate.AirVRClientFailed("failed to init AirVRClient : " + result);
        }
        licenseFile.Release();

        _stateMachine = new AirVRClientStateMachine(this, _profile.delayToResumePlayback);
    }