add allow_custom_value attitude

app.py

@@ -113,6 +113,7 @@ with gr.Blocks(
                 label="Model",
                 choices=get_available_models(),
                 value=None,
+                allow_custom_value=True,
             )
             rt_pitch = gr.Slider(-12, 12, value=0, step=1, label="Pitch")
             rt_index_rate = gr.Slider(0, 1, value=0.75, step=0.05, label="Index Rate")