Issue with iSight since upgrading to ML

I've been using my MBA 2011 without any issues at all ever since I bought it last Summer. However, I recently upgraded to Mountain Lion and I've not dropped or damaged my laptop in any possible way or anything but it won't detect iSight at all. No matter what program I open it says no camera detected.

I've tried resetting the SMC and PRAM. Done all the various things, but I just don't see how this can happen out of nowhere? I've lately been searching about this issue and it seems a lot of people experience issues with iSight after upgrading as well.

Have you experienced any issues or know something that might help me as my warranty has obviously expired.