From a50b2b3d8e2cc3a9f0035221be703b45b05632ff Mon Sep 17 00:00:00 2001
From: Bryce Boe <bbzbryce@gmail.com>
Date: Sun, 20 Sep 2026 15:52:13 -0700
Subject: [PATCH] Fix duplicate ID3 tag when tagging TTS audio (#182800)

---
 homeassistant/components/tts/__init__.py |   1 +
 tests/components/tts/fixtures/tagged.mp3 | Bin 0 -> 957 bytes
 tests/components/tts/test_init.py        |  27 ++++++++++++++++++++++-
 3 files changed, 27 insertions(+), 1 deletion(-)
 create mode 100644 tests/components/tts/fixtures/tagged.mp3

diff --git a/homeassistant/components/tts/__init__.py b/homeassistant/components/tts/__init__.py
index 71adc8a98752..7a876c31d20d 100644
--- a/homeassistant/components/tts/__init__.py
+++ b/homeassistant/components/tts/__init__.py
@@ -1212,6 +1212,7 @@ class SpeechManager:
                     tts_file["artist"] = artist
                     tts_file["album"] = album
                     tts_file["title"] = message
+                data_bytes.seek(0)
                 tts_file.save(data_bytes)
         except mutagen.MutagenError as err:
             _LOGGER.error("ID3 tag error: %s", err)
diff --git a/tests/components/tts/fixtures/tagged.mp3 b/tests/components/tts/fixtures/tagged.mp3
new file mode 100644
index 0000000000000000000000000000000000000000..b29b59e5add726e01930b985422cee4e8ef6c071
GIT binary patch
literal 957
zcmeZtF=k-^0p*b3U{@f`&%nU!lUSB!W~65bL<UA+SqSm}bISoZ*E26IAIJf!XJ7^D
znZOW-3EHrL^;p1lEZ{#D0J0qDxMZN?j4VJL7*JsefH0XSh+TM74--bC|9?(70u*BQ
r0EzoJ`nraOhJq+#pg#?OY<dHbdum|rfm%N59z-k*h44YRmi{aNnh8BC

literal 0
HcmV?d00001

diff --git a/tests/components/tts/test_init.py b/tests/components/tts/test_init.py
index fba4caa26e65..e6402ce2e786 100644
--- a/tests/components/tts/test_init.py
+++ b/tests/components/tts/test_init.py
@@ -44,7 +44,13 @@ from .common import (
     retrieve_media,
 )
 
-from tests.common import MockModule, async_mock_service, mock_integration, mock_platform
+from tests.common import (
+    MockModule,
+    async_mock_service,
+    load_fixture_bytes,
+    mock_integration,
+    mock_platform,
+)
 from tests.typing import ClientSessionGenerator, WebSocketGenerator
 
 ORIG_WRITE_TAGS = tts.SpeechManager.write_tags
@@ -2302,3 +2308,22 @@ async def test_stream_override_with_conversion(
         assert wav_reader.readframes(wav_reader.getnframes()) == bytes(
             22050 * 2 * 2
         )  # 1 second @ 22.5Khz/stereo
+
+
+def test_write_tags_keeps_single_id3_tag() -> None:
+    """Test tagging audio that already carries an ID3 tag does not add a second one."""
+    data = load_fixture_bytes("tagged.mp3", DOMAIN)
+    assert data.startswith(b"ID3")
+    assert data.count(b"ID3") == 1
+
+    tagged = ORIG_WRITE_TAGS(
+        "42f18378fd4393d18c8dd11d03fa9563c1e54491_en-us_-_test.mp3",
+        data,
+        "Test",
+        "There is someone at the door.",
+        "en",
+        None,
+    )
+
+    assert tagged.startswith(b"ID3")
+    assert tagged.count(b"ID3") == 1