diff --git a/phoneuse/wechat_hook_send.py b/phoneuse/wechat_hook_send.py
index 6383290..880ab7f 100644
--- a/phoneuse/wechat_hook_send.py
+++ b/phoneuse/wechat_hook_send.py
@@ -286,15 +286,26 @@ def _tts_to_silk(text: str, voice: str, tmp_dir: str) -> tuple[str, int]:
     asyncio.run(_synth())
 
     # 2. ffmpeg → PCM16LE 16kHz mono
-    if not shutil.which("ffmpeg"):
+    # shutil.which misses Termux bin when running under root su; probe extra paths
+    _FFMPEG_CANDIDATES = ["ffmpeg",
+                          "/data/data/com.termux/files/usr/bin/ffmpeg",
+                          "/usr/bin/ffmpeg", "/usr/local/bin/ffmpeg"]
+    ffmpeg_bin = next((p for p in _FFMPEG_CANDIDATES if shutil.which(p) or
+                       (os.path.isfile(p) and os.access(p, os.X_OK))), None)
+    if not ffmpeg_bin:
         raise RuntimeError("ffmpeg not found: (Termux) pkg install ffmpeg")
     subprocess.run(
-        ["ffmpeg", "-y", "-i", mp3, "-ar", "16000", "-ac", "1", "-f", "s16le", pcm],
+        [ffmpeg_bin, "-y", "-i", mp3, "-ar", "16000", "-ac", "1", "-f", "s16le", pcm],
         check=True, capture_output=True
     )
 
     # 3. Node.js silk-wasm → SILK V3 (already includes \x02#!SILK_V3 prefix)
-    if not shutil.which("node"):
+    _NODE_CANDIDATES = ["node",
+                        "/data/data/com.termux/files/usr/bin/node",
+                        "/usr/bin/node", "/usr/local/bin/node"]
+    node_bin = next((p for p in _NODE_CANDIDATES if shutil.which(p) or
+                     (os.path.isfile(p) and os.access(p, os.X_OK))), None)
+    if not node_bin:
         raise RuntimeError("node not found: (Termux) pkg install nodejs")
 
     # Locate silk-wasm: check global npm, then openclaw bundle
@@ -315,7 +326,7 @@ silk.encode(fs.readFileSync('{pcm}'), 16000).then(function(r) {{
     process.stdout.write(String(r.duration));
 }}).catch(function(e) {{ process.stderr.write(String(e)); process.exit(1); }});
 """
-    r = subprocess.run(["node", "-e", node_script], capture_output=True, text=True, timeout=60)
+    r = subprocess.run([node_bin, "-e", node_script], capture_output=True, text=True, timeout=60)
     if r.returncode != 0:
         raise RuntimeError(f"silk-wasm encode failed: {r.stderr or r.stdout}. "
                            "Install: npm install -g silk-wasm")
@@ -357,32 +368,10 @@ def send_voice_tts_via_hook(
         except Exception as e:
             return {"status": "error", "error": f"TTS/SILK generation failed: {e}"}
 
-        wechat_cache = "/data/data/com.tencent.mm/cache/hook_voice_src.amr"
-        if _ON_DEVICE:
-            stage = _root_sh(
-                f'cp "{silk_path}" "{wechat_cache}" && '
-                f'chmod 644 "{wechat_cache}" && '
-                f'chown u0_a330:u0_a330 "{wechat_cache}"'
-            )
-        else:
-            adb = _adb_prefix()
-            remote_tmp = "/sdcard/hook_voice_tts_tmp.amr"
-            subprocess.run(adb + ["push", silk_path, remote_tmp],
-                           check=True, capture_output=True)
-            stage = _root_sh(
-                f'cp "{remote_tmp}" "{wechat_cache}" && '
-                f'chmod 644 "{wechat_cache}" && '
-                f'chown u0_a330:u0_a330 "{wechat_cache}" && '
-                f'rm -f "{remote_tmp}"'
-            )
-
-        if stage.returncode != 0:
-            return {"status": "error",
-                    "error": f"failed to stage SILK: {stage.stderr or stage.stdout}"}
-
-    # TemporaryDirectory is cleaned up; wechat_cache is intact
-    result = send_voice_via_hook(wxid=wxid, silk_path=wechat_cache,
-                                  duration_ms=duration_ms)
+        # Delegate staging + broadcast to send_voice_via_hook (it handles both
+        # on-device and off-device paths). Must call while tmp dir is still alive.
+        result = send_voice_via_hook(wxid=wxid, silk_path=silk_path,
+                                     duration_ms=duration_ms)
     result["tts_text"] = text[:100]
     result["tts_voice"] = voice
     return result