[Django]-WAV file from user microphone vs. WAV file from file: Some difference is causing bugs, but what are these different?

The sound file you’re creating is 32-bit PCM, which is an arguably non-standard audio codec. Chrome supports it (source) but Firefox does not (source, bug).

Encode it as 16-bit PCM and it’ll be universally acceptable.

EDIT: As mentioned in the comments, this is the parameter in question.