diff --git a/tests/controls/slidertest.cpp b/tests/controls/slidertest.cpp
index 771cd16a08..8d84c2ea52 100644
--- a/tests/controls/slidertest.cpp
+++ b/tests/controls/slidertest.cpp
@@ -112,7 +112,7 @@ void SliderTestCase::LineUpDown()
     EventCounter linedown(m_slider, wxEVT_SCROLL_LINEDOWN);
 
     wxUIActionSimulator sim;
-
+    wxYield();
     m_slider->SetFocus();
 
     sim.Char(WXK_UP);
@@ -129,6 +129,7 @@ void SliderTestCase::LinePageSize()
 {
 #if wxUSE_UIACTIONSIMULATOR
     wxUIActionSimulator sim;
+    wxYield();
     m_slider->SetFocus();
 
     m_slider->SetPageSize(20);