diff --git a/src/slic3r/GUI/Widgets/Scrollbar.cpp b/src/slic3r/GUI/Widgets/Scrollbar.cpp
index 2eac9f1bf..b71390b83 100644
--- a/src/slic3r/GUI/Widgets/Scrollbar.cpp
+++ b/src/slic3r/GUI/Widgets/Scrollbar.cpp
@@ -270,10 +270,13 @@ void MyScrollbar::OnMouseWheel(wxMouseEvent &event)
 {
 	int dMotion, actualDim;
 	if (event.GetWheelRotation() > 0)
-		dMotion = -m_pixelsPerUnit;
+		//dMotion = -m_pixelsPerUnit;
+        dMotion = -SCROLL_D_MOTION;
 	else 
-		dMotion = m_pixelsPerUnit;
-	m_previousMouse += dMotion;
+		// dMotion = m_pixelsPerUnit;
+        dMotion = SCROLL_D_MOTION;
+		
+	//m_previousMouse += dMotion;
 	actualDim = m_actualDim;
 
 	if (m_direction == wxVSCROLL)
diff --git a/src/slic3r/GUI/Widgets/Scrollbar.hpp b/src/slic3r/GUI/Widgets/Scrollbar.hpp
index eab7aaa77..9b00eaedc 100644
--- a/src/slic3r/GUI/Widgets/Scrollbar.hpp
+++ b/src/slic3r/GUI/Widgets/Scrollbar.hpp
@@ -9,6 +9,7 @@
 #endif
 
 enum {BEFORE_SCROLLBAR, ON_SCROLLBAR, AFTER_SCROLLBAR, NOWHERE};
+#define SCROLL_D_MOTION 4
 
 class ScrolledWindow;