From 0663bbc2fbda20aacccbf623d78b6de149f07c43 Mon Sep 17 00:00:00 2001
From: Om Chauhan <omchauhan64408@gmail.com>
Date: Wed, 31 Dec 2025 08:33:17 +0530
Subject: [PATCH 1/2] added encoding validation in DeepgramTTSService

---
 src/pipecat/services/deepgram/tts.py | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/src/pipecat/services/deepgram/tts.py b/src/pipecat/services/deepgram/tts.py
index fb52b05e8..82fd31cfd 100644
--- a/src/pipecat/services/deepgram/tts.py
+++ b/src/pipecat/services/deepgram/tts.py
@@ -51,6 +51,8 @@ class DeepgramTTSService(WebsocketTTSService):
     message for conversational AI use cases.
     """
 
+    SUPPORTED_ENCODINGS = ("linear16", "mulaw", "alaw")
+
     def __init__(
         self,
         *,
@@ -68,9 +70,17 @@ class DeepgramTTSService(WebsocketTTSService):
             voice: Voice model to use for synthesis. Defaults to "aura-2-helena-en".
             base_url: WebSocket base URL for Deepgram API. Defaults to "wss://api.deepgram.com".
             sample_rate: Audio sample rate in Hz. If None, uses service default.
-            encoding: Audio encoding format. Defaults to "linear16".
+            encoding: Audio encoding format. Defaults to "linear16". Must be one of SUPPORTED_ENCODINGS.
             **kwargs: Additional arguments passed to parent InterruptibleTTSService class.
+
+        Raises:
+            ValueError: If encoding is not in SUPPORTED_ENCODINGS.
         """
+        if encoding.lower() not in self.SUPPORTED_ENCODINGS:
+            raise ValueError(
+                f"Unsupported encoding '{encoding}'. Must be one of {', '.join(self.SUPPORTED_ENCODINGS)} for WebSocket TTS."
+            )
+
         super().__init__(
             sample_rate=sample_rate,
             pause_frame_processing=True,

From bd6afd445d3bd2dbda8a1b5553c9508be5afb9dd Mon Sep 17 00:00:00 2001
From: Om Chauhan <omchauhan64408@gmail.com>
Date: Wed, 31 Dec 2025 09:18:18 +0530
Subject: [PATCH 2/2] added changelog

---
 changelog/3329.changed.md | 1 +
 1 file changed, 1 insertion(+)
 create mode 100644 changelog/3329.changed.md

diff --git a/changelog/3329.changed.md b/changelog/3329.changed.md
new file mode 100644
index 000000000..8271decf2
--- /dev/null
+++ b/changelog/3329.changed.md
@@ -0,0 +1 @@
+- Added encoding validation to `DeepgramTTSService` to prevent unsupported encodings from reaching the API. The service now raises `ValueError` at initialization with a clear error message.