Problems with YouTube Following Adobe Flash Player Update

Hello,
Since downloading the latest flash player from adobe, I'm finding that videos in YouTube, when accessed through Firefox, keep giving an error message of 'an error occurred please try later.' Yet if I go to GoogleChrome, the same video plays. Although I have noted that Chrome is unresponsive on the first attempt in Chrome. Has anyone else come across this and knows the solution? I've tried all the usual tricks of uninstalling/reinstalling, clearing cache etc. I'm not a big YouTube user, but when I go there I want the thing to work. It's really annoying!
I'm using Windows 7 home edition. Firefox 16.0.1. I'm not sure the version of Chrome but its the most upto date one as I deinstalled that and reinstalled it again.

Can anyone help?