Daniel65 wrote:
I'm asking for my sister, who has an Acer (I think) Laptop that has been
upgraded from Win 8.0 to 8.1 to 10 and makes use of Facebook group
Video-chat thingee.

Previously, when she has Video chatted, she can see and hear others and
they can see her, but not hear her, so she has to type in her responses
so others can then read them.

I duckduckgo'd for her "Enabling microphone in Windows 10" which brought
up lots of responses. Looking at the first selection, "How to Enable /
Turn On Microphone in Windows 10", she gave those suggestions a bit of a
go, but failed to improve her situation ...... because she says her
sound does work, i.e. she can, apparently, say "stuff" and record that
"stuff" and play that "stuff" back .... it's just that the "stuff" does
not get out on to the Internet!

Does anyone here have any suggestions as to what she could try, please??

On Windows 10, you have to "enable" the webcam on a per-App basis.
Whereas Win32 programs have a single tick box to turn them on.

As if your desktop computer or laptop computer, was a cellphone.

Check and make sure the camera and microphone are enabled.

The Facebook Video-chat could be working via the web browser
being used. Like perhaps WEBRTC protocol over Firefox. You would
enable the webcam for usage with Firefox. And that would mean
a "video" preference of some sort, as well as a "sound" preference.

Since your sister seems to have working video (people can see her),
that suggests the permissions are sufficiently enabled for the job.

I tested now with VLC (videolan.org) and did capture
from the camera, and got a VLC entry in the Privacy
section of the Windows 10 Settings wheel (lower left sidebar).

Windows 10 2004 is worse, in terms of "warm feelings" about
what is going on. At least in previous versions, there was
a more "picky" interface. Whereas the confirmation of info
in the current interface, leaves a bit to be desired.

It's possible Facebook doesn't have a "test link" for testing
purposes. Some of the others do. Zoom had a test page. My
medical system had a test page for their video conference.
But not every company is clued in when it comes to things
like that (Facebook).

https://i.postimg.cc/RCP3ZWmx/webcam-adjust.gif

Paul