tests never play the finish tink out loud

tests/conftest.py

@@ -26,6 +26,16 @@ def _no_real_device(monkeypatch):
     monkeypatch.setattr(device_sync, "find_device", lambda: None)
 
 
+@pytest.fixture(autouse=True)
+def _no_real_sound(monkeypatch):
+    """No test may play the finish "tink" out loud: every test that runs an
+    export, sync or import to the end used to, and trav hears it while the
+    suite runs. Tests about the sound patch ``_tink`` themselves."""
+    from unittest.mock import MagicMock
+    from lintunes.gui import sounds
+    monkeypatch.setattr(sounds, "_tink", MagicMock())
+
+
 @pytest.fixture(scope="session")
 def qapp():
     """A Qt application so QObject/QTimer and real widgets work in tests.