Index: /trunk/src/VBox/Main/xml/Settings.cpp
===================================================================
--- /trunk/src/VBox/Main/xml/Settings.cpp	(revision 35150)
+++ /trunk/src/VBox/Main/xml/Settings.cpp	(revision 35151)
@@ -1009,5 +1009,6 @@
     pelmMedium->setAttributePath("location", mdm.strLocation);
 
-    pelmMedium->setAttribute("format", mdm.strFormat);
+    if (devType == DeviceType_HardDisk || RTStrICmp(mdm.strFormat.c_str(), "RAW"))
+        pelmMedium->setAttribute("format", mdm.strFormat);
     if (mdm.fAutoReset)
         pelmMedium->setAttribute("autoReset", mdm.fAutoReset);