Hello Andy,

>> 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 ;-(.

> Was it using the correct mic?

It was the only one connected.

> my laptop has its inbuilt mic, the sound card input and when docked on
> my desk it also has a mic in the USB webcam and a mic input from a USB
> audio in/out box ... sometimes software picks the wrong input.

I understand, and I did know that kind of wrong input selections.
But the Pi 4B has no audio input on the MoBo,
only a socket for an extra camera on a flatcable, which I do not have.
The most logical idea could be that Raspbian Buster Linux does not have a
USB2A mic audio in software module, and can only work with the camera on
the motherboard socket if connected?
May be there is a "hidden" solution to change over from internal camera
to the USB2A version, I do not know of?

It is even more strange that de USB cam is working ok, but the built in mic
on the same USB2A device is also been seen,
hence I could not give it allowance,
but still gives no sound and that error on the testsites.

Are there other Linux versions working on a Pi 4B both 4GB and 8GB
that have the GUI and the Chrome webbrowser I can give a try?
Zoom prefers Chrome above other webbrowsers.

Henri.
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