.

providers/tts.py

@@ -166,7 +166,12 @@ class ElevenLabsTTS(BaseTTS):
             self._voice_settings,
         )
 
-    async def synthesize_stream(self, text_stream: AsyncIterable[str]) -> AsyncGenerator[bytes, None]:
+    async def synthesize_stream(
+        self,
+        text_stream: AsyncIterable[str],
+        *,
+        language_code: str | None = None,
+    ) -> AsyncGenerator[bytes, None]:
         if not self._api_key:
             raise RuntimeError("ELEVENLABS_API_KEY is required for ElevenLabs TTS")
         if not self._voice_id:
@@ -178,7 +183,8 @@ class ElevenLabsTTS(BaseTTS):
         except Exception as exc:  # noqa: BLE001
             raise RuntimeError("The `websockets` package is required for ElevenLabs TTS WebSocket streaming") from exc
 
-        websocket_url = self._build_websocket_url()
+        effective_language_code = (str(language_code).strip() if language_code else "") or self._language_code
+        websocket_url = self._build_websocket_url(language_code=effective_language_code)
         started_monotonic = time.perf_counter()
         audio_chunk_count = 0
         audio_byte_count = 0
@@ -193,7 +199,7 @@ class ElevenLabsTTS(BaseTTS):
             self._output_format,
             self._provider_sample_rate_hz,
             self._target_sample_rate_hz,
-            self._language_code,
+            effective_language_code,
             self._auto_mode,
         )
         try:
@@ -290,7 +296,7 @@ class ElevenLabsTTS(BaseTTS):
         except OSError as exc:
             raise RuntimeError("ElevenLabs TTS WebSocket connection failed") from exc
 
-    def _build_websocket_url(self) -> str:
+    def _build_websocket_url(self, *, language_code: str | None = None) -> str:
         query = {
             "model_id": self._model_id,
             "output_format": self._output_format,
@@ -299,8 +305,9 @@ class ElevenLabsTTS(BaseTTS):
             "sync_alignment": "false",
             "apply_text_normalization": "auto",
         }
-        if self._language_code:
-            query["language_code"] = self._language_code
+        effective_language = (str(language_code).strip() if language_code else "") or self._language_code
+        if effective_language:
+            query["language_code"] = effective_language
         encoded_voice_id = quote(self._voice_id, safe="")
         return f"{self._ws_base}/v1/text-to-speech/{encoded_voice_id}/stream-input?{urlencode(query)}"