Logitech QuickCam Pro 4000

[pharsea]

I have been able to use VLC media player with my Raspberry-Pi 2B and Logitech QuickCam Pro 4000 successfully for some time.

Recently, I updated the Raspberian Operating System.

rpi-update
apt-get install rpi-update

I may have thereby updated the "firmware", but am not sure.


VLC then started to misbehave. In particular the WebCam stopped adjusting to low-light levels.
When I attempted to manually adjust the brightness the WebCam locked up and all I got was a dark screen.
I then re-installed the Raspbian OS but I suspect that the "firmware" remained updated even so.

I then transferred the WebCam to my windows 10 PC. It started working normally with VLC there.
I then reconnected it to my R-pi and it worked OK - except that it would not auto-adjust to low light levels.
When I once more attempted manual control, the WebCam locked-up again.
This time when I connected it up to my PC it did not start working. In fact VLC hung!

I then rebooted my PC - but this was problematic!
After a long delay I got a windows error message saying something was wrong with a device driver.
The PC then rebooted and my WebCam worked again with VLC under Windows 10.
I then reconnected the WebCam to my R-Pi and it worked again, but did not adjust to low-light levels.

I deduce from the above observations that:

1. There is some incompatibiliy between my WebCam, VLC and the OS I am using.
2. The WebCam has some kind of internal configuration which is preserved even when it is not pwered.
3. This internal configuration can get into an invalid state.
4. The Raspbian OS cannot "heal" this device malaise, but Windows 10 can do - and does, automatically.

Please, either tell me how I can get my webCam to work properly.