Isight on Macbook Pro no longer functions... Hardware failure or software?

Question

I have seen others having this issue as well, and I have tried the fixes I have seen in other threads on the forum.
It was working with Photobooth just fine after I recieved it, and it seems over time at some point it quit working. I remember seeing the green LED stay lit for some time after using and closing photobooth at one time, but I just ignored it, and after rebooting it wasn't working.
I was able to shut down and get it working, and now it doesn't work at all.
I have reset the PMU several times, and that gives me a different response from the operating system every time I do it...
If i start Photobooth or Ichat, it will just act as if there is a camera there, but no picture... If I reset the PMU, reboot, and run those apps, it says the camera is in use, with nothing loaded except the OS. If I reset the PMU again and reboot, I get no error again, with no video. I just keeps cycling like that.
Could bootcamp have killed my Isight in some way? I haven't loaded anything but generic XP Sp2, and I haven't clicked on the camera device that causes bluescreens apparently...

Answer 1

Since you've already reset your PMU (and presumably your NVRAM as well) during the reset process I don't think there is any more "user serviceable" steps you can take. I'm unclear why you are not able to downgrade your firmware, but since I have not done this myself (and don't currently have my MBP to test it with) I can't walk you through the process. I did find one other user replying that this firmware restore CD will only work if the previous firmware upgrade was interrupted.
"Note: This CD cannot be used to return an Intel-based Macintosh computer's firmware to a previous version if a successful update has already been performed."
I guess this means there is no simple way to do it.
Do you have anything else plugged into your USB bus? If you try to plug other devices in, do you see them show up OK in your hardware profiles? Does your iSight show up there as well?
Does anyone know if the little privacy screen which floats ontop of the camera has any software hooks, or if its just a simple cover?
I actually use an external iSight with my MBP for doing recordings of my educational morning classes because I like the way it sits flat on the table and can be moved around without adjusting the laptop-- I'm assuming you don't have one to test with.
Its probably time to work with Apple Support -- there may not be anything else you can do on your own at this point. Worst case scenario, you'll be without a machine for a week or so.
Golan.