diff --git a/pycyphal/transport/can/media/candump/_candump.py b/pycyphal/transport/can/media/candump/_candump.py
index c68de56d..66e1d85e 100644
--- a/pycyphal/transport/can/media/candump/_candump.py
+++ b/pycyphal/transport/can/media/candump/_candump.py
@@ -146,7 +146,10 @@ def close(self) -> None:
             self._f.close()
             self._thread, thd = None, self._thread
             assert thd is not None
-            thd.join(timeout=1)
+            try:
+                thd.join(timeout=1)
+            except RuntimeError:
+                pass
 
     @property
     def _is_closed(self) -> bool:
diff --git a/pycyphal/transport/can/media/pythoncan/_pythoncan.py b/pycyphal/transport/can/media/pythoncan/_pythoncan.py
index 119859d1..04f2af2c 100644
--- a/pycyphal/transport/can/media/pythoncan/_pythoncan.py
+++ b/pycyphal/transport/can/media/pythoncan/_pythoncan.py
@@ -323,9 +323,15 @@ def close(self) -> None:
         self._closed = True
         try:
             self._tx_queue.put(None)
-            self._tx_thread.join(timeout=self._MAXIMAL_TIMEOUT_SEC * 10)
+            try:
+                self._tx_thread.join(timeout=self._MAXIMAL_TIMEOUT_SEC * 10)
+            except RuntimeError:
+                pass
             if self._maybe_thread is not None:
-                self._maybe_thread.join(timeout=self._MAXIMAL_TIMEOUT_SEC * 10)
+                try:
+                    self._maybe_thread.join(timeout=self._MAXIMAL_TIMEOUT_SEC * 10)
+                except RuntimeError:
+                    pass
                 self._maybe_thread = None
         finally:
             try:
diff --git a/pycyphal/transport/can/media/socketcan/_socketcan.py b/pycyphal/transport/can/media/socketcan/_socketcan.py
index 6dad9a06..17d68562 100644
--- a/pycyphal/transport/can/media/socketcan/_socketcan.py
+++ b/pycyphal/transport/can/media/socketcan/_socketcan.py
@@ -165,7 +165,10 @@ def close(self) -> None:
             if self._ctl_main.fileno() >= 0:  # Ignore if already closed.
                 self._ctl_main.send(b"stop")  # The actual data is irrelevant, we just need it to unblock the select().
             if self._maybe_thread:
-                self._maybe_thread.join(timeout=_SELECT_TIMEOUT)
+                try:
+                    self._maybe_thread.join(timeout=_SELECT_TIMEOUT)
+                except RuntimeError:
+                    pass
                 self._maybe_thread = None
         finally:
             self._sock.close()  # These are expected to be idempotent.
diff --git a/pycyphal/transport/can/media/socketcand/_socketcand.py b/pycyphal/transport/can/media/socketcand/_socketcand.py
index d011d48a..0a382eb8 100644
--- a/pycyphal/transport/can/media/socketcand/_socketcand.py
+++ b/pycyphal/transport/can/media/socketcand/_socketcand.py
@@ -203,9 +203,15 @@ def close(self) -> None:
         self._closed = True
         try:
             self._tx_queue.put(None)
-            self._tx_thread.join(timeout=self._MAXIMAL_TIMEOUT_SEC * 10)
+            try:
+                self._tx_thread.join(timeout=self._MAXIMAL_TIMEOUT_SEC * 10)
+            except RuntimeError:
+                pass
             if self._maybe_thread is not None:
-                self._maybe_thread.join(timeout=self._MAXIMAL_TIMEOUT_SEC * 10)
+                try:
+                    self._maybe_thread.join(timeout=self._MAXIMAL_TIMEOUT_SEC * 10)
+                except RuntimeError:
+                    pass
                 self._maybe_thread = None
         finally:
             try:
diff --git a/tests/demo/_demo_app.py b/tests/demo/_demo_app.py
index ea7cd802..a3ed15b4 100644
--- a/tests/demo/_demo_app.py
+++ b/tests/demo/_demo_app.py
@@ -310,7 +310,7 @@ async def _unittest_slow_demo_app(
             assert hb.health.value == hb.health.NOMINAL
             assert hb.mode.value == hb.mode.OPERATIONAL
             assert num_heartbeats <= hb.uptime <= 300
-            assert prev_hb_transfer[0].uptime <= hb.uptime <= prev_hb_transfer[0].uptime + 1
+            assert prev_hb_transfer[0].uptime <= hb.uptime <= prev_hb_transfer[0].uptime + 2  # +2 due to aliasing
             assert transfer.transfer_id == prev_hb_transfer[1].transfer_id + 1
             prev_hb_transfer = hb_transfer
             num_heartbeats += 1
diff --git a/tests/transport/can/media/_pythoncan.py b/tests/transport/can/media/_pythoncan.py
index e4a31395..4e503cd8 100644
--- a/tests/transport/can/media/_pythoncan.py
+++ b/tests/transport/can/media/_pythoncan.py
@@ -164,6 +164,7 @@ def _unittest_can_pythoncan_iface_name() -> None:
     # multiple colons are allowed in interface names, only the first one is split
     media = PythonCANMedia("virtual:0:0", 1_000_000)
     assert media.interface_name == "virtual:0:0"
+    media.close()
 
 
 def _unittest_can_pythoncan_errors() -> None: