Detect insertion and removal of USB Sound cards

    using System;
    using System.Management;
    using Microsoft.Win32;

    public class DeviceDetector : IDisposable
    {
        #region Variables

        private ManagementEventWatcher insertWatcher;
        private ManagementEventWatcher removeWatcher;
        private readonly Guid GUID_DEVCLASS_MEDIA = new Guid("{4D36E96C-E325-11CE-BFC1-08002BE10318}");

        public delegate void DeviceInsertedHandler(object sender, DeviceChangedEventArgs eventArgs);

        public event DeviceInsertedHandler DeviceInserted;

        public delegate void DeviceRemovedHandler(object sender, DeviceChangedEventArgs eventArgs);

        public event DeviceRemovedHandler DeviceRemoved;

        #endregion

        #region Constructors

        public DeviceDetector()
        {
            EstablishWatchedEvents();
        }

        #endregion

        #region Private Methods

        private void EstablishWatchedEvents()
        {
            // setup the query to monitor insertion
            const string qryInsertion = "SELECT * FROM __InstanceCreationEvent " +
                                        "WITHIN 2 " +
                                        "WHERE TargetInstance ISA 'Win32_PnPEntity'";
            insertWatcher = new ManagementEventWatcher(qryInsertion);
            insertWatcher.EventArrived += insertWatcher_EventArrived;
            insertWatcher.Start();


            // setup the query to monitor removal
            const string qryRemoval = "SELECT TargetInstance " +
                                      "FROM __InstanceDeletionEvent " +
                                      "WITHIN 2 " +
                                      "WHERE TargetInstance ISA 'Win32_PnPEntity' ";

            removeWatcher = new ManagementEventWatcher(qryRemoval);
            removeWatcher.EventArrived += removeWatcher_EventArrived;
            removeWatcher.Start();
        }



        private string GetDeviceName(string deviceID)
        {
            string[] Parts = deviceID.Split(@"\".ToCharArray());
            if (Parts.Length >= 3)
            {
                string DevType = Parts[0];
                string DeviceInstanceId = Parts[1];
                string DeviceUniqueID = Parts[2];
                string RegPath = @"SYSTEM\CurrentControlSet\Enum\" + DevType + "\\" + DeviceInstanceId + "\\" +
                                 DeviceUniqueID;
                RegistryKey key = Registry.LocalMachine.OpenSubKey(RegPath);
                if (key != null)
                {
                    object result = key.GetValue("FriendlyName");
                    if (result != null)
                        return result.ToString();

                }
            }
            return String.Empty;
        }

        #endregion

        #region Events

        private void insertWatcher_EventArrived(object sender, EventArrivedEventArgs e)
        {
            var mbo = (ManagementBaseObject) e.NewEvent["TargetInstance"];
            if (new Guid((string) mbo["ClassGuid"]) == GUID_DEVCLASS_MEDIA)
            {
                var deviceName = (string) mbo["Name"];
                if (deviceName.Length <= 0) return;

                if (DeviceInserted != null)
                    DeviceInserted(this, new DeviceChangedEventArgs {DeviceName = deviceName});

            }
        }

        private void removeWatcher_EventArrived(object sender, EventArrivedEventArgs e)
        {
            var mbo = (ManagementBaseObject) e.NewEvent.Properties["TargetInstance"].Value;
            string deviceName = GetDeviceName(mbo.Properties["DeviceID"].Value.ToString());
            if (deviceName.Length <= 0) return;

            if (DeviceRemoved != null)
                DeviceRemoved(this, new DeviceChangedEventArgs {DeviceName = deviceName});
        }

        #endregion

        #region Implemented Methods

        public void Dispose()
        {
            insertWatcher.Stop();
            removeWatcher.Stop();

            insertWatcher.Dispose();
            removeWatcher.Dispose();
        }

        #endregion
    }

    public class DeviceChangedEventArgs : EventArgs
    {
        public string DeviceName { get; set; }
    }
    // Usage
    private DeviceDetector deviceDetector;

    private void Init()
    {
        deviceDetector= new DeviceDetector();
        deviceDetector.DeviceInserted += deviceDetector_DeviceInserted;
        deviceDetector.DeviceRemoved += deviceDetector_DeviceRemoved;
    }

    private void Terminate()
    {
        deviceDetector.Dispose();
    }

    void deviceDetector_DeviceInserted(object sender, DeviceChangedEventArgs eventArgs)
    {
        Debug.WriteLine("Device Inserted: " + eventArgs.DeviceName);
    }

    void deviceDetector_DeviceRemoved(object sender, DeviceChangedEventArgs eventArgs)
    {
        Debug.WriteLine("Device Removed: " + eventArgs.DeviceName);
    }