[0.2.4.0] Garbled audio when exporting mp3 from mp4?

[MaZZly]

Expected Behavior

Audio extracted to mp3 should sound like in video

Actual Behavior

Low volume and weird sounds.
Video: https://sample-videos.com/video123/mp4/720/big_buck_bunny_720p_30mb.mp4
Extracted audio: https://www.dropbox.com/s/czytk0pudmn4xj7/bad-audio.mp3?dl=1

Steps to Reproduce the Problem

with VideoFileClip('big_buck_bunny_720p_30mb.mp4') as clip:
   clip.audio.write_audiofile('out.mp3')

Specifications

• Python Version: 2.7.12
• Moviepy Version: 0.2.4.0
• Platform Name: Ubuntu
• Platform Version: 18.04

[MaZZly]

Does not happen on 0.2.3.5

[MaZZly]

Same thing also happens if opening a working mp3 as AudioFileClip and doing write_audiofile()

[Zulko]

Yes it is the same system at play.

What happened here is that Numpy was throwing warnings that "np.fromstring" is deprecated and should be replaced by "np.frombuffer" when converting a blob to an array. I must have broken something in the convertion.