diff --git a/app/web/app.js b/app/web/app.js
index 1fbd409..95c7cd3 100644
--- a/app/web/app.js
+++ b/app/web/app.js
@@ -79,16 +79,46 @@ function _makeUtterance(text, lang) {
   return u;
 }
 
+// Hat der Browser nutzbare Sprachstimmen? (Linux-Desktops haben oft KEINE -> stumm.)
+function deviceVoicesReady() {
+  if (!TTS_SUPPORTED) return false;
+  if (!_voices.length) loadVoices();
+  return _voices.length > 0;
+}
+
+// Server-Fallback: holt Audio via /api/speak (ohne tts_provider -> Server-Default,
+// niemals "device") und spielt es ab. Greift, wenn Geräte-TTS keine Stimme hat.
+async function serverSpeakFallback(text, lang, btn) {
+  try {
+    const body = { text };
+    if (lang) body.language = lang;
+    const r = await fetch("/api/speak", {
+      method: "POST", headers: { "Content-Type": "application/json" },
+      body: JSON.stringify(body),
+    });
+    if (!r.ok) throw new Error("HTTP " + r.status);
+    startReplay([await r.arrayBuffer()], btn);
+  } catch (e) {
+    setReplayPlaying(btn, false);
+    statusEl.textContent = "Vorlesen fehlgeschlagen";
+  }
+}
+
 // Vorlesen ohne Button-Status (automatisches Vorlesen der Antwort).
 function deviceSpeak(text, lang) {
-  if (!TTS_SUPPORTED || !text) return;
-  speechSynthesis.cancel();
-  speechSynthesis.speak(_makeUtterance(text, lang));
+  if (!text) return;
+  if (deviceVoicesReady()) {
+    speechSynthesis.cancel();
+    speechSynthesis.speak(_makeUtterance(text, lang));
+  } else {
+    serverSpeakFallback(text, lang, null);   // keine Stimmen -> Server-Audio
+  }
 }
 
 // Vorlesen mit Button-Status (Replay): Icon -> ⏹ während des Sprechens, danach zurück.
 function deviceSpeakBtn(text, lang, btn) {
-  if (!TTS_SUPPORTED || !text) { setReplayPlaying(btn, false); return; }
+  if (!text) { setReplayPlaying(btn, false); return; }
+  if (!deviceVoicesReady()) { serverSpeakFallback(text, lang, btn); return; }
   speechSynthesis.cancel();
   const u = _makeUtterance(text, lang);
   u.onend = u.onerror = () => setReplayPlaying(btn, false);
diff --git a/app/web/index.html b/app/web/index.html
index 18f2b28..002d30f 100644
--- a/app/web/index.html
+++ b/app/web/index.html
@@ -318,6 +318,6 @@
     <div id="status" class="w-full max-w-3xl mx-auto mt-1 min-h-[1rem] text-xs text-slate-500 dark:text-slate-400"></div>
   </footer>
 
-  <script src="/app.js?v=38"></script>
+  <script src="/app.js?v=39"></script>
 </body>
 </html>