enable concurrency

app.py

@@ -227,7 +227,7 @@ with gr.Blocks(css=css) as demo:
         fn=infer,
         inputs=[video_in, chosen_model],
         outputs=[audio_o, video_o],
-        #concurrency_limit = 2
+        concurrency_limit = 2
     )
 
 demo.queue(max_size=10).launch(show_api=False, debug=True, show_error=True)