Index: /trunk/src/VBox/Main/src-server/HostUSBDeviceImpl.cpp
===================================================================
--- /trunk/src/VBox/Main/src-server/HostUSBDeviceImpl.cpp	(revision 41812)
+++ /trunk/src/VBox/Main/src-server/HostUSBDeviceImpl.cpp	(revision 41813)
@@ -1379,5 +1379,9 @@
                         /* Take action if we're supposed to attach it to a VM. */
                         if (mUniState == kHostUSBDeviceState_AttachingToVM)
+                        {
+                            alock.release();
                             attachToVM(mMachine, mMaskedIfs);
+                            alock.acquire();
+                        }
                         break;
 
@@ -1468,5 +1472,4 @@
 
     return fIsImportant;
-
 }