Index: /trunk/src/VBox/Frontends/VirtualBox/src/runtime/UIFrameBuffer.cpp
===================================================================
--- /trunk/src/VBox/Frontends/VirtualBox/src/runtime/UIFrameBuffer.cpp	(revision 55726)
+++ /trunk/src/VBox/Frontends/VirtualBox/src/runtime/UIFrameBuffer.cpp	(revision 55727)
@@ -1532,5 +1532,5 @@
             /* Fast scale sub-pixmap (2nd copy involved): */
             subPixmap = subPixmap.scaled(subPixmap.size() * dBackingScaleFactor,
-                                         Qt::IgnoreAspectRatio, transformationMode(enmScalingOptimizationType));
+                                         Qt::IgnoreAspectRatio, Qt::FastTransformation);
         }