Index: /trunk/src/VBox/Storage/testcase/tstVDIo.cpp
===================================================================
--- /trunk/src/VBox/Storage/testcase/tstVDIo.cpp	(revision 56572)
+++ /trunk/src/VBox/Storage/testcase/tstVDIo.cpp	(revision 56573)
@@ -678,4 +678,8 @@
 static uint64_t tstVDIoGetSpeedKBs(uint64_t cbIo, uint64_t tsNano)
 {
+    /* Seen on one of the testboxes, avoid division by 0 below. */
+    if (tsNano == 0)
+        return 0;
+
     /*
      * Blow up the value until we can do the calculation without getting 0 as