Why does python module wave work with errors in cgi script?

Question

Python

I tested everything well locally - it works with a bang, and when accessing the script via cgi (after a slight modification to work in this mode), the following errors occur:

• wrong sample rate (sounds much higher in pitch)
  
• glitches that don't appear in the local version
  

I checked it many times, everything is generated correctly from the console, and after cgi execution, at least the sample rate in the file parameter is correct, but the sound is higher.
Maybe someone knows - is this a bug in the wave module, or are there any tweaks that allow you to configure cgi as it should?
UPD. Script function - generate .wav file from several local