diff --git a/src/Backends/Banshee.Gio/Banshee.Hardware.Gio/UsbDevice.cs b/src/Backends/Banshee.Gio/Banshee.Hardware.Gio/UsbDevice.cs
index f5d7976..436dabe 100644
--- a/src/Backends/Banshee.Gio/Banshee.Hardware.Gio/UsbDevice.cs
+++ b/src/Backends/Banshee.Gio/Banshee.Hardware.Gio/UsbDevice.cs
@@ -73,7 +73,9 @@ namespace Banshee.Hardware.Gio
         public static int GetBusNumber (IUsbDevice device)
         {
             var raw = device as IRawDevice;
-            return raw == null ? 0 : int.Parse (raw.Device.UdevMetadata.GetPropertyString (UdevUsbBusNumber));
+            var udevbusnumber = raw.Device.UdevMetadata.GetPropertyString (UdevUsbBusNumber);
+
+            return raw == null || udevbusnumber == null ? 0 : int.Parse (udevbusnumber);
         }
 
         public static int GetDeviceNumber (IUsbDevice device)
