audio_bytes should be uploaded_file.getvalue()

app.py

@@ -3,6 +3,6 @@ import streamlit as st
 if __name__ == "__main__":
   uploaded_file = st.file_uploader("Choose a file")
   if uploaded_file is not None:
-    with open(uploaded_file, 'rb') as audio_file:
-      audio_bytes = audio_file.read()
-      st.audio(audio_bytes, format='audio/wav')
+    audio_bytes = uploaded_file.getvalue()
+#    audio_bytes = audio_file.read()
+    st.audio(audio_bytes, format='audio/wav')