diff --git a/tests/test_tap_humanize.py b/tests/test_tap_humanize.py
index 9f4bfef..d2080de 100644
--- a/tests/test_tap_humanize.py
+++ b/tests/test_tap_humanize.py
@@ -36,3 +36,15 @@ def test_tap_enabled_jitters_within_radius(monkeypatch):
         set_rng(None)
     px, py = driver.calls[-1][1]
     assert abs(px - 10) <= 5.0 and abs(py - 20) <= 5.0
+    assert (px, py) != (10, 20), "jitter must move the point"
+
+    # second call with fresh seed must differ from first
+    set_rng(random.Random(12))
+    try:
+        driver2 = FakeDriver()
+        tap(10, 20, manager=_connected(driver2))
+    finally:
+        set_rng(None)
+    px2, py2 = driver2.calls[-1][1]
+    assert (px2, py2) != (10, 20)
+    assert (px2, py2) != (px, py), "consecutive calls with different seeds must produce different jitter"