diff --git a/pyproject.toml b/pyproject.toml
index 0940a88..169f31c 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -5,6 +5,7 @@ description = "Realtime voice assistant with WebSocket audio gateway, streaming
 readme = "README.md"
 requires-python = ">=3.12"
 dependencies = [
+    "anyio>=4.15.1,<5",
     "deepagents>=0.7.26",
     "fastapi>=0.141.1",
     "httpx>=0.28,<1",
diff --git a/src/voice_assistant/audio_gateway/app/main.py b/src/voice_assistant/audio_gateway/app/main.py
index af2717d..22325af 100644
--- a/src/voice_assistant/audio_gateway/app/main.py
+++ b/src/voice_assistant/audio_gateway/app/main.py
@@ -35,6 +35,7 @@ Architecture:
 import json
 import logging
 from pathlib import Path
+import anyio
 
 from fastapi.responses import FileResponse
 from fastapi.staticfiles import StaticFiles
@@ -1044,93 +1045,93 @@ async def audio_socket(websocket: WebSocket) -> None:
         pass
 
     finally:
-        # Stop Gateway-owned finalization before provider cleanup.
-        try:
-            await cancel_finalization_task()
-        except Exception:
-            logger.exception(
-                "Failed to cancel finalization task. session_id=%s",
-                session.session_id if session else None,
-            )
-
-        # Cancel and await the task owned by VoicePipeline.
-        if pipeline is not None:
+        with anyio.CancelScope(shield=True):
+            # Stop Gateway-owned finalization before provider cleanup.
             try:
-                await pipeline.cancel_turn_task()
+                await cancel_finalization_task()
             except Exception:
                 logger.exception(
-                    "Failed to cancel voice turn task. session_id=%s",
+                    "Failed to cancel finalization task. session_id=%s",
                     session.session_id if session else None,
                 )
 
-        # A task may have been created before registration failed.
-        # Handle it independently if the pipeline does not own it.
-        if stt_events_task is not None:
-            task = stt_events_task
-
-            if (
-                pipeline is None
-                or pipeline.turn_task is not task
-            ):
+            # Cancel and await the task owned by VoicePipeline.
+            if pipeline is not None:
                 try:
-                    if not task.done():
-                        task.cancel()
-
-                    try:
-                        await asyncio.wait_for(
-                            asyncio.shield(task),
-                            timeout=5.0,
-                        )
-                    except asyncio.CancelledError:
-                        if not task.cancelled():
-                            raise
-
-                except TimeoutError:
-                    logger.error(
-                        "Unregistered STT task cleanup timed out. "
-                        "session_id=%s",
-                        session.session_id if session else None,
-                    )
+                    await pipeline.cancel_turn_task()
                 except Exception:
                     logger.exception(
-                        "Failed to clean up unregistered STT task. "
-                        "session_id=%s",
+                        "Failed to cancel voice turn task. session_id=%s",
                         session.session_id if session else None,
                     )
 
-                if task.done():
-                    stt_events_task = None
-        # Abort STT without waiting for a final transcript.
-        if stt is not None:
+            # Handle tasks created before pipeline registration.
+            if stt_events_task is not None:
+                task = stt_events_task
+
+                if (
+                    pipeline is None
+                    or pipeline.turn_task is not task
+                ):
+                    try:
+                        if not task.done():
+                            task.cancel()
+
+                        try:
+                            await asyncio.wait_for(
+                                asyncio.shield(task),
+                                timeout=5.0,
+                            )
+                        except asyncio.CancelledError:
+                            if not task.cancelled():
+                                raise
+
+                    except TimeoutError:
+                        logger.error(
+                            "Unregistered STT task cleanup timed out. "
+                            "session_id=%s",
+                            session.session_id if session else None,
+                        )
+                    except Exception:
+                        logger.exception(
+                            "Failed to clean up unregistered STT task. "
+                            "session_id=%s",
+                            session.session_id if session else None,
+                        )
+
+                    if task.done():
+                        stt_events_task = None
+
+            # Abort STT without waiting for a final transcript.
+            if stt is not None:
+                try:
+                    await stt.abort_session()
+                except Exception:
+                    logger.exception(
+                        "Failed to abort STT session. session_id=%s",
+                        session.session_id if session else None,
+                    )
+
+            # Release session and semantic turn state.
             try:
-                await stt.abort_session()
+                if pipeline is not None:
+                    pipeline.close_session()
+                elif session is not None:
+                    session.close()
             except Exception:
                 logger.exception(
-                    "Failed to abort STT session. session_id=%s",
+                    "Failed to close voice session. session_id=%s",
                     session.session_id if session else None,
                 )
 
-        # Release session and semantic turn state.
-        try:
-            if pipeline is not None:
-                pipeline.close_session()
-            elif session is not None:
-                session.close()
-        except Exception:
-            logger.exception(
-                "Failed to close voice session. session_id=%s",
-                session.session_id if session else None,
-            )
-
-        # Release provider-owned HTTP connections.
-        if agent is not None:
-            try:
-                await close_optional_provider(agent)
-            except Exception:
-                logger.exception(
-                    "Failed to close Agent provider. session_id=%s",
-                    session.session_id if session else None,
-                )
-            finally:
-                agent = None
-
+            # Release provider-owned HTTP connections.
+            if agent is not None:
+                try:
+                    await close_optional_provider(agent)
+                except Exception:
+                    logger.exception(
+                        "Failed to close Agent provider. session_id=%s",
+                        session.session_id if session else None,
+                    )
+                finally:
+                    agent = None
\ No newline at end of file
diff --git a/uv.lock b/uv.lock
index 173ce6b..ed41543 100644
--- a/uv.lock
+++ b/uv.lock
@@ -2924,6 +2924,7 @@ name = "voice-assistant"
 version = "0.1.0"
 source = { editable = "." }
 dependencies = [
+    { name = "anyio" },
     { name = "deepagents" },
     { name = "fastapi" },
     { name = "httpx" },
@@ -2946,6 +2947,7 @@ dev = [
 
 [package.metadata]
 requires-dist = [
+    { name = "anyio", specifier = ">=4.15.1,<5" },
     { name = "deepagents", specifier = ">=0.7.26" },
     { name = "fastapi", specifier = ">=0.141.1" },
     { name = "httpx", specifier = ">=0.28,<1" },