I'm getting a lot of problem reports about the new Logitech QuickCam zoom model (with USB product ID 0x08B4). I'm not sure what the problem is, but I've mailed Logitech about it and I hope to get a reply soon.
The basic symptom is that when the camera is plugged in it's detected alright, you can open it but as soons as video starts streaming you get a lot of USB ISOC errors and nothing gets through; something the module even crashes. At first I thought it was related to PWC 8.12 and kernel 2.4.22, but then I noticed that nearly all bug reports mention a QuickCam Zoom. So, if you recently acquired this type of webcam and you have problems using it under Linux, you know you're not the only one.
Currently, I have no solution for you yet. In case you do have this camera working, I'd like to hear about itm including a short description of your setup (kernel, output of 'lspci -v' and /proc/bus/usb/device), purchase date and serial number.
In case you have trouble, there's no point mailing me about it, not even asking when I will have a solution for you. In case I have one, it will be posted on this site.