Why is this AudioWorklet to MP3 code producing different results on Chromium and Firefox?

[guest271314]

I'm running the same code on Firefox 125 and Chromium 124.

The code run on Firefox produces a Blob that is an encoded MP3 file - after chopping up whatever audio is being played in Firefox while the audio is finalizing encoding.

The Chromium version produces an MP3 that is full of glitches, clipping, and plays back faster.

Here's a link to a ZIP file containing the result examples https://github.com/guest271314/MP3Recorder/files/14625262/firefox125_chromium124_audioworklet_to_mp3.zip.

Here's a link to the source code https://github.com/guest271314/MP3Recorder/blob/main/MP3Recorder.js.