Using mulaw audio buffer data

[boblp]

I created a question here in stackoverflow: (transform mulaw 8000khz audio buffer data into valid bytes format) with more the details.

But basically I want to be able to send my mulaw audio buffer variable but im unsure on why I keep getting:

raise ValueError(
    "Soundfile is either not in the correct format or is malformed. Ensure that the soundfile has "
    "a valid audio file extension (e.g. wav, flac or mp3) and is not corrupted. If reading from a remote "
    "URL, ensure that the URL is the full address to **download** the audio file."
)

Am I missing something? When I send bytes from a wav file it does work properly...