Index: /trunk/src/VBox/Main/xml/Settings.cpp
===================================================================
--- /trunk/src/VBox/Main/xml/Settings.cpp	(revision 55231)
+++ /trunk/src/VBox/Main/xml/Settings.cpp	(revision 55232)
@@ -5504,4 +5504,5 @@
              * from the default for old settings.
              * AHCI ports are hotpluggable by default every other device is not.
+             * Also check if there are USB storage controllers.
              */
             for (StorageControllersList::const_iterator it = storageMachine.llStorageControllers.begin();
@@ -5511,4 +5512,11 @@
                 bool fSettingsBumped = false;
                 const StorageController &sctl = *it;
+
+                if (sctl.controllerType == StorageControllerType_USB)
+                {
+                    m->sv = SettingsVersion_v1_15;
+                    fSettingsBumped = true;
+                    break;
+                }
 
                 for (AttachedDevicesList::const_iterator it2 = sctl.llAttachedDevices.begin();
@@ -5534,4 +5542,7 @@
             }
 
+            /*
+             * Check if there is an xHCI (USB3) USB controller.
+             */
             for (USBControllerList::const_iterator it = hardwareMachine.usbSettings.llUSBControllers.begin();
                  it != hardwareMachine.usbSettings.llUSBControllers.end();