fix bugs on video stream react.js page

I am looking for a skilled React developer who can help me fix bugs in the React Video Recorder using the mp4-muxer library.

Important : You must have two cameras connected to your pc otherwise don't bid.

Overview
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The app is running here : https://videoo-capture-hk5ku2vhva-uc.a.run.app/

Here is what we have right now :
- A video and screen recorder using React
- Output n number of videos in MP4 format
- The recorder has 4K or HD capabilities for high-quality recordings wherever the input device supports.


BUGS TO FIX
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1. Choppy audio.
2. When a Second video input device, presentation shows primary video input device, but twice.
3. Screen recordings, multiple stream recording stress testing ends up with Matroska container, it is not mp4 stream, it should be mp4 container.
4 . AV sync issues for different framerates 24, 25, 30, 50, 60, there should not be any AV Sync issues.


Follow these steps to reproduce "Choppy audio, missing audio slices issue":
1. Start a webcam recording
2. Wait for one minute.
3. Download the recorded content.
4. You can hear the audio have choppy output, where there are gaps in every audio frame.