It has been known that many of Logitech's UVC webcams do not work well under Linux due to a specific firmware bug. Several developers of the linux-uvc project have been trying to hammer out a software workaround with limited success. I hope to have some time in the coming days to run a software-only USB analyzer on a Windows laptop to give us more insight into this problem. Please go to this link to find the latest USB retry patch:

http://www.mail-archive.com/linux-uvc-devel@lists.berlios.de/msg00386.html

 
UPDATE: I have used SnoopyPro 0.22 to capture the USB traffic from the camera when it was started and stopped. I have uploaded two separate files, one binary and one text, but the binary file is much more complete.

Logitech Quick Cam Ultra Vision (text)
Logitech Quick Cam Ultra Vision (binary) 

UPDATE 2: It seems that the Logitech Firmware bug is there for good and cannot be worked around in the UVC driver. The long term fix is to hack up the Linux USB subsystem to provide a work-around but that might (will) not happen at any time in the future. Logitech has dropped the ball on this product!