diff --git a/DeviceController.py b/DeviceController.py
index 6cb96be..107917d 100644
--- a/DeviceController.py
+++ b/DeviceController.py
@@ -47,7 +47,7 @@ class DeviceController:
                     self.running = False
                 elif cmd == "mode":
                     ch, mode = arg               # ch: 0 (A) / 1 (B)
-                    self.dev.set_mode(ch, mode)
+                    self.set_mode(ch, mode)
             except queue.Empty:
                 pass