diff --git a/src/options_panel_widgets.py b/src/options_panel_widgets.py
index de1f969..cd1a27d 100644
--- a/src/options_panel_widgets.py
+++ b/src/options_panel_widgets.py
@@ -873,6 +873,11 @@ def update(self, event=None, shock=None):
         if sender in [parent.unc_shading_box, parent.wavelet_levels_box]:
             parent.plot.signal.unc_shading = parent.unc_shading_box.currentText()
             parent.plot.signal.wavelet_levels = parent.wavelet_levels_box.value()
+            if parent.plot.signal.unc_shading != 'Smoothed Signal':
+                parent.wavelet_levels_box.setEnabled(False)
+            else:
+                parent.wavelet_levels_box.setEnabled(True)
+
             parent.plot.signal.update_uncertainty_shading()
 
         if sender in self.boxes['unc_cutoff']: