Speculative fix for a sometimes speech crash bug.

src/fenrirscreenreader/core/outputManager.py

@@ -22,6 +22,8 @@ class OutputManager:
         self.interrupt_thread = None
         self.interrupt_done = None
         self.interrupt_wait_timeout = 0.1
+        self.speech_driver_lock = threading.Lock()
+        self.speech_driver_lock_timeout = 0.05
 
     def initialize(self, environment):
         self.env = environment
@@ -159,6 +161,15 @@ class OutputManager:
             return
         if interrupt or flush:
             self.interrupt_output()
+        if not self.speech_driver_lock.acquire(
+            timeout=self.speech_driver_lock_timeout
+        ):
+            self.env["runtime"]["DebugManager"].write_debug_out(
+                "OutputManager.speak_text: Speech driver busy, dropping speech",
+                debug.DebugLevel.WARNING,
+            )
+            return
+        try:
             try:
                 self.env["runtime"]["SpeechDriver"].set_language(
                     self.env["runtime"]["SettingsManager"].get_setting(
@@ -213,9 +224,9 @@ class OutputManager:
 
             try:
                 self.env["runtime"]["SpeechDriver"].set_rate(
-                self.env["runtime"]["SettingsManager"].get_setting_as_float(
+                    self.env["runtime"][
-                    "speech", "rate"
+                        "SettingsManager"
-                )
+                    ].get_setting_as_float("speech", "rate")
                 )
             except Exception as e:
                 self.env["runtime"]["DebugManager"].write_debug_out(
@@ -243,9 +254,9 @@ class OutputManager:
 
             try:
                 self.env["runtime"]["SpeechDriver"].set_volume(
-                self.env["runtime"]["SettingsManager"].get_setting_as_float(
+                    self.env["runtime"][
-                    "speech", "volume"
+                        "SettingsManager"
-                )
+                    ].get_setting_as_float("speech", "volume")
                 )
             except Exception as e:
                 self.env["runtime"]["DebugManager"].write_debug_out(
@@ -264,9 +275,9 @@ class OutputManager:
                 else:
                     clean_text = text.replace("\n", " ")
 
-            clean_text = self.env["runtime"]["TextManager"].replace_head_lines(
+                clean_text = self.env["runtime"][
-                clean_text
+                    "TextManager"
-            )
+                ].replace_head_lines(clean_text)
                 clean_text = self.process_mid_word_punctuation(clean_text)
                 clean_text = self.env["runtime"][
                     "PunctuationManager"
@@ -280,11 +291,14 @@ class OutputManager:
                 )
             except Exception as e:
                 self.env["runtime"]["DebugManager"].write_debug_out(
-                '"speak" in OutputManager.speak_text ', debug.DebugLevel.ERROR
+                    '"speak" in OutputManager.speak_text ',
+                    debug.DebugLevel.ERROR,
                 )
                 self.env["runtime"]["DebugManager"].write_debug_out(
                     str(e), debug.DebugLevel.ERROR
                 )
+        finally:
+            self.speech_driver_lock.release()
 
     def interrupt_output(self, wait=True):
         interrupt_done, started = self.start_interrupt_output()
@@ -320,6 +334,15 @@ class OutputManager:
                     self.interrupt_running = False
 
     def cancel_speech(self):
+        if not self.speech_driver_lock.acquire(
+            timeout=self.speech_driver_lock_timeout
+        ):
+            self.env["runtime"]["DebugManager"].write_debug_out(
+                "OutputManager interrupt_output: Speech driver busy, "
+                "skipping interrupt",
+                debug.DebugLevel.WARNING,
+            )
+            return
         try:
             self.env["runtime"]["SpeechDriver"].cancel()
             self.env["runtime"]["DebugManager"].write_debug_out(
@@ -331,6 +354,8 @@ class OutputManager:
                 + str(e),
                 debug.DebugLevel.ERROR,
             )
+        finally:
+            self.speech_driver_lock.release()
 
     def play_sound_icon(self, sound_icon="", interrupt=True):
         if sound_icon == "":

src/fenrirscreenreader/fenrirVersion.py

@@ -4,5 +4,5 @@
 # Fenrir TTY screen reader
 # By Chrys, Storm Dragon, and contributors.
 
-version = "2026.05.18"
+version = "2026.05.19"
 code_name = "testing"

tests/unit/test_output_manager.py

@@ -26,6 +26,14 @@ def build_output_manager():
             "SoundDriver": sound_driver,
             "SpeechDriver": speech_driver,
             "DebugManager": Mock(write_debug_out=Mock()),
+            "TextManager": Mock(
+                replace_head_lines=Mock(side_effect=lambda text: text)
+            ),
+            "PunctuationManager": Mock(
+                proceed_punctuation=Mock(
+                    side_effect=lambda text, _ignore_punctuation: text
+                )
+            ),
         },
     }
     return output_manager, sound_driver, speech_driver
@@ -122,6 +130,40 @@ def test_interrupt_output_waits_only_briefly_for_slow_cancel():
         output_manager.interrupt_thread.join(timeout=1.0)
 
 
+@pytest.mark.unit
+def test_cancel_speech_skips_when_speech_driver_is_busy():
+    output_manager, _sound_driver, speech_driver = build_output_manager()
+    output_manager.speech_driver_lock_timeout = 0.01
+    output_manager.speech_driver_lock.acquire()
+
+    try:
+        start_time = time.monotonic()
+        output_manager.cancel_speech()
+        elapsed = time.monotonic() - start_time
+    finally:
+        output_manager.speech_driver_lock.release()
+
+    assert elapsed < 0.2
+    speech_driver.cancel.assert_not_called()
+
+
+@pytest.mark.unit
+def test_speak_text_drops_speech_when_cancel_holds_driver_lock():
+    output_manager, _sound_driver, speech_driver = build_output_manager()
+    output_manager.speech_driver_lock_timeout = 0.01
+    output_manager.speech_driver_lock.acquire()
+
+    try:
+        start_time = time.monotonic()
+        output_manager.speak_text("hello", interrupt=False, flush=False)
+        elapsed = time.monotonic() - start_time
+    finally:
+        output_manager.speech_driver_lock.release()
+
+    assert elapsed < 0.2
+    speech_driver.speak.assert_not_called()
+
+
 @pytest.mark.unit
 def test_key_interrupt_command_uses_nonblocking_interrupt():
     module = load_key_interrupt_module()

tests/unit/test_remote_instance_registry.py

@@ -0,0 +1,35 @@
+import json
+import time
+
+from fenrirscreenreader.core import remoteInstanceRegistry
+
+
+def test_write_instance_prunes_stale_registry_files(tmp_path, monkeypatch):
+    monkeypatch.setattr(
+        remoteInstanceRegistry, "get_registry_dir", lambda: str(tmp_path)
+    )
+    monkeypatch.setattr(
+        remoteInstanceRegistry,
+        "process_exists",
+        lambda pid: pid == 456,
+    )
+
+    stale_instance = tmp_path / "123.json"
+    stale_instance.write_text(
+        json.dumps(
+            {
+                "pid": 123,
+                "updated_at": time.time(),
+            }
+        )
+        + "\n",
+        encoding="utf-8",
+    )
+    invalid_instance = tmp_path / "invalid.json"
+    invalid_instance.write_text("not json\n", encoding="utf-8")
+
+    remoteInstanceRegistry.write_instance({"pid": 456})
+
+    assert not stale_instance.exists()
+    assert not invalid_instance.exists()
+    assert (tmp_path / "456.json").exists()