Index: /trunk/src/VBox/HostDrivers/VBoxUSB/darwin/VBoxUSB.cpp
===================================================================
--- /trunk/src/VBox/HostDrivers/VBoxUSB/darwin/VBoxUSB.cpp	(revision 57971)
+++ /trunk/src/VBox/HostDrivers/VBoxUSB/darwin/VBoxUSB.cpp	(revision 57972)
@@ -194,4 +194,6 @@
     static void  scheduleReleaseByOwner(RTPROCESS Owner);
 private:
+    /** Padding to guard against parent class expanding (see class remarks). */
+    uint8_t m_abPadding[256];
     /** The interface we're driving (aka. the provider). */
     IOUSBDevice *m_pDevice;
@@ -1090,5 +1092,6 @@
      */
     IOService *pRet = IOUSBUserClientInit::probe(pProvider, pi32Score);
-    Assert(pRet == this);
+    /*AssertMsg(pRet == this, ("pRet=%p this=%p *pi32Score=%d \n", pRet, this, pi32Score ? *pi32Score : 0)); - call always returns NULL on 10.11+ */
+    pRet = this;
     m_Owner = Owner;
     m_uId = uId;