diff --git a/pytec/pytec/gui/view/ctrl_panel.py b/pytec/pytec/gui/view/ctrl_panel.py
index 9ccbb05..9e04a55 100644
--- a/pytec/pytec/gui/view/ctrl_panel.py
+++ b/pytec/pytec/gui/view/ctrl_panel.py
@@ -75,16 +75,17 @@ class CtrlPanel(QObject):
             for ch in range(self.NUM_CHANNELS)
         ]
 
-        for i, tree in enumerate(self.trees_ui):
+        for ch, tree in enumerate(self.trees_ui):
             tree.setHeaderHidden(True)
-            tree.setParameters(self.params[i], showTop=False)
-            self.params[i].setValue = self._setValue
-            self.params[i].sigTreeStateChanged.connect(sigTreeStateChanged_handle)
+            tree.setParameters(self.params[ch], showTop=False)
+            self.params[ch].setValue = self._setValue
+            self.params[ch].sigTreeStateChanged.connect(sigTreeStateChanged_handle)
 
             set_tree_label_tips(tree)
 
-            for handle in sigActivated_handles[i]:
-                self.params[i].child(*handle[0]).sigActivated.connect(handle[1])
+            for handle in sigActivated_handles[ch]:
+                self.params[ch].child(*handle[0]).sigActivated.connect(handle[1])
+
 
     def _setValue(self, value, blockSignal=None):
         """