Update app.py

app.py

@@ -1,5 +1,5 @@
 # app.py - Demucs + Basic-Pitch pipeline -> multi-track MIDI (Gradio)
-# Author: AlexGPT
+# Author: MrblackDev
 # WARNING: heavy deps (demucs, basic-pitch, torch, tensorflow). Use a beefy Space or local env.
 
 import os
@@ -245,7 +245,7 @@ with gr.Blocks(css=CSS, title="Demucs + BasicPitch -> Multi-MIDI") as demo:
                 "<div id='app_subtitle'>Demucs (stems) + Basic-Pitch (polyphonic) pipeline. Fallbacks included.</div>")
     with gr.Row():
         with gr.Column(scale=2):
-            audio_in = gr.Audio(source="upload", type="filepath", label="Audio (mix) - WAV/MP3")
+            audio_in = gr.Audio(sources=["upload"], type="filepath", label="Audio (mix) - WAV/MP3")
             demucs_model = gr.Dropdown(["htdemucs_ft","htdemucs","htdemucs_6s","mdx","mdx_extra"], value=DEMucs_MODEL_NAME, label="Demucs model")
             use_basic = gr.Checkbox(value=True, label="Use Basic-Pitch for stems (if available)")
             run_btn = gr.Button("🚀 Run pipeline")