diff --git a/CHANGELOG.md b/CHANGELOG.md
index aa7636f0a07..595366d2e35 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -122,6 +122,7 @@ Docs: https://docs.openclaw.ai
 - CLI/agents: keep `openclaw agents list --json` on the config-only path by default, avoiding bundled plugin loading unless callers request `--bindings`. Fixes #71739. Thanks @kaloster.
 - Plugins/install: force plugin dependency installs to stay project-local even when inherited npm config requests global installs, so successful installs still materialize the plugin's staged `node_modules`.
 - Providers/Google: transcode Gemini TTS PCM to Opus for voice-note targets so WhatsApp and other native voice-note replies can play as voice messages.
+- TTS/WhatsApp: mark non-Opus provider output as voice-note intent so channel delivery transcodes MP3/WebM replies to Ogg/Opus PTT audio.
 - Plugins/runtime deps: reuse existing external bundled-plugin stage roots when mirrored plugin roots are inspected again, avoiding second-generation `openclaw-unknown-*` stages and repeated first-turn restaging. Fixes #71599.
 - iOS/macOS Talk Mode: allow `talk.speechLocale` to set the speech recognition locale for non-English voice conversations. Fixes #44688.
 - Plugins/providers: honor explicit plugin candidate lists instead of reading a persisted registry snapshot from local state, keeping candidate-scoped provider discovery hermetic.
diff --git a/docs/tools/tts.md b/docs/tools/tts.md
index 7e2e9adc8ff..3d6ea28e21d 100644
--- a/docs/tools/tts.md
+++ b/docs/tools/tts.md
@@ -754,10 +754,11 @@ These override the effective config from `messages.tts` plus the active
 
 - **Feishu / Matrix / Telegram / WhatsApp**: voice-note replies prefer Opus (`opus_48000_64` from ElevenLabs, `opus` from OpenAI).
   - 48kHz / 64kbps is a good voice message tradeoff.
-- **Feishu**: when a voice-note reply is produced as MP3/WAV/M4A or another
-  likely audio file, the Feishu plugin transcodes it to 48kHz Ogg/Opus with
-  `ffmpeg` before sending the native `audio` bubble. If conversion fails, Feishu
-  receives the original file as an attachment.
+- **Feishu / WhatsApp**: when a voice-note reply is produced as MP3/WAV/M4A or
+  another likely audio file, the channel plugin transcodes it to 48kHz Ogg/Opus
+  with `ffmpeg` before sending the native voice message. If conversion fails,
+  Feishu receives the original file as an attachment; WhatsApp send fails rather
+  than posting an incompatible PTT payload.
 - **Other channels**: MP3 (`mp3_44100_128` from ElevenLabs, `mp3` from OpenAI).
   - 44.1kHz / 128kbps is the default balance for speech clarity.
 - **MiniMax**: MP3 (`speech-2.8-hd` model, 32kHz sample rate) for normal audio attachments. For voice-note targets such as Feishu and Telegram, OpenClaw transcodes the MiniMax MP3 to 48kHz Opus with `ffmpeg` before delivery.
@@ -844,8 +845,8 @@ Notes:
 The `tts` tool converts text to speech and returns an audio attachment for
 reply delivery. When the channel is Feishu, Matrix, Telegram, or WhatsApp,
 the audio is delivered as a voice message rather than a file attachment.
-Feishu can transcode non-Opus TTS output on this path when `ffmpeg` is
-available.
+Feishu and WhatsApp can transcode non-Opus TTS output on this path when
+`ffmpeg` is available.
 WhatsApp sends visible text separately from PTT voice-note audio because clients
 do not consistently render captions on voice notes.
 It accepts optional `channel` and `timeoutMs` fields; `timeoutMs` is a
diff --git a/extensions/speech-core/src/tts.test.ts b/extensions/speech-core/src/tts.test.ts
index 149ecb84a31..0249d178467 100644
--- a/extensions/speech-core/src/tts.test.ts
+++ b/extensions/speech-core/src/tts.test.ts
@@ -71,7 +71,12 @@ async function expectTtsPayloadResult(params: {
   text: string;
   target: "voice-note" | "audio-file";
   audioAsVoice: true | undefined;
+  providerResult?: MockSpeechSynthesisResult;
+  mediaExtension?: string;
 }) {
+  if (params.providerResult) {
+    synthesizeMock.mockResolvedValueOnce(params.providerResult);
+  }
   const cfg = createTtsConfig(params.prefsName);
   let mediaDir: string | undefined;
   try {
@@ -84,7 +89,7 @@ async function expectTtsPayloadResult(params: {
 
     expect(synthesizeMock).toHaveBeenCalledWith(expect.objectContaining({ target: params.target }));
     expect(result.audioAsVoice).toBe(params.audioAsVoice);
-    expect(result.mediaUrl).toMatch(/voice-\d+\.ogg$/);
+    expect(result.mediaUrl).toMatch(new RegExp(`voice-\\d+\\.${params.mediaExtension ?? "ogg"}$`));
 
     mediaDir = result.mediaUrl ? path.dirname(result.mediaUrl) : undefined;
   } finally {
@@ -118,35 +123,26 @@ describe("speech-core native voice-note routing", () => {
     });
   });
 
-  it("marks Feishu voice-note TTS for channel-side transcoding when provider returns mp3", async () => {
-    synthesizeMock.mockResolvedValueOnce({
-      audioBuffer: Buffer.from("mp3"),
-      outputFormat: "mp3",
-      fileExtension: ".mp3",
-      voiceCompatible: false,
-    });
-    const cfg = createTtsConfig("openclaw-speech-core-tts-feishu-mp3-test");
-    let mediaDir: string | undefined;
-    try {
-      const result = await maybeApplyTtsToPayload({
-        payload: { text: "This Feishu reply should be transcoded by the channel." },
-        cfg,
-        channel: "feishu",
-        kind: "final",
+  it.each(["feishu", "whatsapp"] as const)(
+    "marks %s voice-note TTS for channel-side transcoding when provider returns mp3",
+    async (channel) => {
+      expect(_test.supportsTranscodedVoiceNoteTts(channel)).toBe(true);
+      await expectTtsPayloadResult({
+        channel,
+        prefsName: `openclaw-speech-core-tts-${channel}-mp3-test`,
+        text: `This ${channel} reply should be transcoded by the channel.`,
+        target: "voice-note",
+        audioAsVoice: true,
+        mediaExtension: "mp3",
+        providerResult: {
+          audioBuffer: Buffer.from("mp3"),
+          outputFormat: "mp3",
+          fileExtension: ".mp3",
+          voiceCompatible: false,
+        },
       });
-
-      expect(synthesizeMock).toHaveBeenCalledWith(
-        expect.objectContaining({ target: "voice-note" }),
-      );
-      expect(result.audioAsVoice).toBe(true);
-      expect(result.mediaUrl).toMatch(/voice-\d+\.mp3$/);
-      mediaDir = result.mediaUrl ? path.dirname(result.mediaUrl) : undefined;
-    } finally {
-      if (mediaDir) {
-        rmSync(mediaDir, { recursive: true, force: true });
-      }
-    }
-  });
+    },
+  );
 
   it("keeps non-native voice-note channels as regular audio files", async () => {
     await expectTtsPayloadResult({
diff --git a/extensions/speech-core/src/tts.ts b/extensions/speech-core/src/tts.ts
index 0a29d0b1b8a..9133be9d1b1 100644
--- a/extensions/speech-core/src/tts.ts
+++ b/extensions/speech-core/src/tts.ts
@@ -640,7 +640,7 @@ export function setLastTtsAttempt(entry: TtsStatusEntry | undefined): void {
 }
 
 const OPUS_CHANNELS = new Set(["telegram", "feishu", "whatsapp", "matrix", "discord"]);
-const TRANSCODED_VOICE_NOTE_CHANNELS = new Set(["feishu"]);
+const TRANSCODED_VOICE_NOTE_CHANNELS = new Set(["feishu", "whatsapp"]);
 
 function resolveChannelId(channel: string | undefined): ChannelId | null {
   return channel ? normalizeChannelId(channel) : null;