In a post on Paul Thurrott’s website, it seems that the problem lies with the changes in the update, in which Microsoft no longer allows USB webcams to stream in MJPEG or H264. Instead they are only allowing YUY2 encoding. This was not a mistake and was done on purpose due to concerns that encoded streams could be duplicated, so Microsoft limited input methods to prevent that from happening.
Users have been reporting that when using their webcams with the likes of Skype, they have run into issues like freezing. The good news is that Microsoft has acknowledged that this could be an issue and that a fix is in the works for a possible release in September, meaning that for now you’ll just have to deal with it.
However there could be a workaround, thanks to Rafael Rivera who tweeted that making some tweaks to the registry should fix it. If you’re not comfortable with making changes you don’t fully understand, maybe you should skip this for now, but if not check it out and see if it works out for you.