change indexing into sig_seg according to AudioSignal

app.py

@@ -58,7 +58,7 @@ def process_fn(input_audio_path, seed, guidance_scale, num_inference_steps):
             end = start + 5.12
 
         # get segment of audio from original file
-        sig_seg = sig[int(start*sig.sample_rate):int(end*sig.sample_rate)]  # int accounts for float end time on last seg
+        sig_seg = sig[..., int(start*sig.sample_rate):int(end*sig.sample_rate)]  # int accounts for float end time on last seg
         print(f"Segment length: {sig_seg.duration}")
         print(f"Segment start: {start}")
         print(f"Segment end: {end}")