diff --git a/tests/test_tray.py b/tests/test_tray.py
index a148a0c..9d1b929 100644
--- a/tests/test_tray.py
+++ b/tests/test_tray.py
@@ -256,10 +256,11 @@ class TestCreateTray:
 
     @pytest.mark.skipif(sys.platform != "linux", reason="Linux-only")
     def test_returns_pystray_on_linux(self):
+        from unittest.mock import MagicMock
         from whisper_local.tray import create_tray
         from whisper_local.tray._tray import PystrayApp
 
-        tray = create_tray(on_settings=lambda: None, on_quit=lambda: None)
+        tray = create_tray(on_settings=MagicMock(), on_quit=MagicMock())
         assert isinstance(tray, PystrayApp)
 
     @pytest.mark.skipif(