feat: warning changed

frontend/index.html

@@ -23,7 +23,7 @@
 
         <!-- Echo warning notice -->
         <div class="echo-warning">
-            ⚠️ No well echo cancellation: Please use headphones with a microphone, or lower your speaker volume to avoid feedback. Otherwise, the captured audio may be affected, which can reduce the accuracy of speech recognition.
+            ⚠️ No echo cancellation: Please use headphones with a microphone. Otherwise, the captured audio may be affected.
         </div>
 
         <!-- Audio Waveforms -->