Before I do

$ pkill pulse audio



the card can be seen on the tab and all all the usual selections are available on that tab.

It is after I do
$ pkill pulse audio
that the tab is empty.

Before
$ pkill pulse audio
no web embedded video or sound plays

After
$ pkill pulse audio
embeded video plays but with no sound



I don't fiddle with settings unless necessary.
For example when I can only get some software with python pip, or I have to install a zip using pacman -U .pkg.tar.gz.
My feeling, tho I'm not certian, is that a package install of some sort messed things up.
I'm not sure when but sometime after January.

I have another identical machine, with more or less the same software, that has video working as it should.
I will, probarly tomorrow, do a packages installed list, on each machine, and compare these.
It might identify some slightly unusual s/w that is installed on this machine.
Who knows. I'll give that ago tomorrow.



--------

I have two more or less identical laptops.
- One of these is the one that has the video playback fail problem.
- On the other the video is working flawlessly.

Earliear this evening I created a package installed list for each machine and did a

$ diff package_list_working_machine package_list_video_playback_fail_machine

and noticed a number of differences.

After removing quite a few packeges from the video playback failing machine, that were not on the working machine, anything that might appear to be to do with video play back, I noticed that packages
pragha
gnome-player
lib-intel-driver
nvidia-utils
nvidia
were installed on the video failing machine but not on the video working machine, amongst many other packages.

So I uninstalled these with

$ sudo pacman -R pragha gnome-player lib-intel-driver nvidia-utils nvidia

and now the video play back and sound works across all applications.

Took a while to find, but got there in the end.

I tried re-installing pragha & gnome-player after the video started working, but video stopped workng again, right after they were installed, so I took them right off again.
I had to re-boot after these two were removed to get video working again.
I have not tested the sensitivity to the other three packages, namely lib-intel-driver, nvidia-utils & nvidia, but I probarly will when I get a moment.
It works out as a lot of re-boots, to work through all the permutations of these 5 packages.

Video is working just now and I will probarly come back to this as I need to as a reference if it fails again.

Hopefully this reference will help others with the same problem.

I think a third party package sucked these packages in my system, becasue I have no memory of ever installing them, though I may have some how mashed this up unwittingly.

All this effort has saved me the dreaded system re-build.

Many thanks to @Shadow_7 for helping me through this.

Thanks also to everyone who contributed and helped with ideas - I would have had to do the dreaded system re-build on this highly customised system without you. Thank you


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