/// <summary>
        /// 再生デバイスを列挙する
        /// </summary>
        private void EnumrateDevices()
        {
            try
            {
                this.PlayerComboBox.Enabled     = false;
                this.mainDeviceComboBox.Enabled = false;
                this.subDeviceComboBox.Enabled  = false;

                var devices = NAudioPlayer.EnumlateDevices();

                // 再生デバイスコンボボックスを設定する
                this.mainDeviceComboBox.DisplayMember = "Name";
                this.mainDeviceComboBox.ValueMember   = "ID";
                this.mainDeviceComboBox.DataSource    = devices.ToArray();

                this.subDeviceComboBox.DisplayMember = "Name";
                this.subDeviceComboBox.ValueMember   = "ID";
                this.subDeviceComboBox.DataSource    = devices.ToArray();

                var defaultDeviceID = devices
                                      .Select(x => x.ID)
                                      .FirstOrDefault() ?? string.Empty;

                if (string.IsNullOrWhiteSpace(TTSYukkuriConfig.Default.MainDeviceID))
                {
                    TTSYukkuriConfig.Default.MainDeviceID = defaultDeviceID;
                }

                if (string.IsNullOrWhiteSpace(TTSYukkuriConfig.Default.SubDeviceID))
                {
                    TTSYukkuriConfig.Default.SubDeviceID = defaultDeviceID;
                }

                if (devices.Count > 0)
                {
                    this.mainDeviceComboBox.SelectedValue = TTSYukkuriConfig.Default.MainDeviceID;
                    this.subDeviceComboBox.SelectedValue  = TTSYukkuriConfig.Default.SubDeviceID;

                    if (string.IsNullOrWhiteSpace(this.mainDeviceComboBox.Text))
                    {
                        this.mainDeviceComboBox.SelectedIndex = 0;
                    }

                    if (string.IsNullOrWhiteSpace(this.subDeviceComboBox.Text))
                    {
                        this.subDeviceComboBox.SelectedIndex = 0;
                    }
                }
            }
            finally
            {
                this.PlayerComboBox.Enabled     = true;
                this.mainDeviceComboBox.Enabled = true;
                this.subDeviceComboBox.Enabled  = this.enabledSubDeviceCheckBox.Checked;
            }
        }