diff --git a/tests/libtest/lib1506.c b/tests/libtest/lib1506.c
index ca1cdc96ff..b61c4db796 100644
--- a/tests/libtest/lib1506.c
+++ b/tests/libtest/lib1506.c
@@ -114,6 +114,7 @@ int test(char *URL)
 
       abort_on_test_timeout();
     }
+    wait_ms(1); /* to ensure different end times */
   }
 
 test_cleanup: