Hello Andy,

>> 
>> says:
>> You are not authorized to use the microphone in your browser.

> Did you get a pop-up microphone permission request from that page,
> before it said "not authorised" ?

Yes, far much before that, when I logged in into a Zoom session and I had to
connect de camera and mic for it.
I had to right click on the HTTPS padlock symbol to allow the Chrome browser
to use both cam and mic. So I did allow them both.
The cam worked ok, but the mic was still silent ;-(.
Then I tried that test site and then came out that it could not be used.
Very strange for 2 identical fresh new USB2 cams inclusiev Mic and given
allowance on both my Pi 4B's, one 4GB and one 8GB.
I tried every possible combination with these 4.

I think there could be 3 problems possible:
1. Chrome for Raspbian does have a bug?
2. Raspbian Buster Linux for de Pi 4B does not have the right sound module?
3. The mic on both the new USB2A cams are defective?

Any idea's?

Henri.

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