Update app.py

app.py

@@ -429,7 +429,7 @@ Example JSON structure:
         
         try:
             combined_audio = AudioSegment.empty()
-            silence_padding = AudioSegment.silent(duration=400)  # 800ms silence
+            silence_padding = AudioSegment.silent(duration=600)  # 800ms silence
             
             for i, audio_file in enumerate(audio_files):
                 try: