Maybe someone with better knowledge of USB can shed some light here:
I have an USB camera that I knew was working several Ubuntu versions ago. But under Karmic and Lucid it refused to work.
I knew that it was listed as supported; but after hours trying things I couldn't make it work.
Then I saw in a forum that someone said that as a final test he disconnected the USB hub and plugged in the camera directly to the computer. After that it worked, so he suspected the hub.
In my case I was connecting directly to the computer already so I thought: "I'll try the other USB port" and the camera worked!!... For a few minutes, then it stopped working.
So it occurred to me that the only difference was that when I switched ports I had disconnected the USB wireless mouse.
I unplugged the mouse and voila! The camera started working under:
This is, everywhere, even Skype!
One clue could be that both devices (the camera and the mouse) are Logitech so the top part of the ID is the same 046d:c50e
Bus 002 Device 006: ID 046d:c50e Logitech, Inc. MX-1000 Cordless Mouse Receiver
Bus 002 Device 003: ID 046d:0870 Logitech, Inc. QuickCam Express
What else could it be the problem here?
Later I will try with this camera in a different computer and also with different mouses.
Do you have any clues for me to investigate or provide better information when reporting the issue?