Index: sources/gui/qml/components/USBButton.qml
===================================================================
diff -u -r73091a6f5717c0fc88e236c06c618ad361f30a3c -r2216ac6ac7f77437a7c29ac8b4043be01bc4609e
--- sources/gui/qml/components/USBButton.qml	(.../USBButton.qml)	(revision 73091a6f5717c0fc88e236c06c618ad361f30a3c)
+++ sources/gui/qml/components/USBButton.qml	(.../USBButton.qml)	(revision 2216ac6ac7f77437a7c29ac8b4043be01bc4609e)
@@ -26,10 +26,12 @@
     x: width - 10
     text.text: qsTr("USB")
     text.font.pixelSize: Fonts.fontPixelButton * 0.75
-    onPressed: {
+    onPressed   : {
         _GuiView.doUSBDriveUmount()
     }
 
+    fading: ! _GuiView.usbReady && ! _GuiView.usbRemoved
+
     Connections { target: _GuiView
         onDidUSBDriveRemove : _root.enabled = false
         onDidUSBDriveMount  : _root.enabled = true