Based on the information you provided, I must agree, it is something with Chrome on the specific PC. If it works perfectly on another PC with Chrome, then I can't think of something else.
New laptops often come with a bunch of extra pre-installed software so it could be something that is causing this, so I would first try by uninstalling (not disabling) any AV software that may be on there.
I also ran a few tests using Chrome 90.0.4430.212 and had no issues.
In regards to Firefox, the truth is that all these WebRTC features are more optimized for Chrome. While Firefox does work, the implementation is not the same from a browser perspective, so just use Chrome. Not a lot we can do about that unfortunately.
Have you tried the new Edge Chromium by any chance? That should offer the same User Experience as Chrome.