I have had problems w/ YouTube Audio(Video is fine)in Firefox lately. I have switched to Google Chrome for YouTube and have had no problems(yet).
Don’t blame the browsers. The issue is the steaming pile of Indian produced code bloat called the Flash Player. 90% of all browser crashes occur because of the Flash Plugin. There is a very real reason why Apple wouldn’t allow it to be installed in their iOS devices.
I can’t wait until all browsers are HTML5 capable and all video sites serve up non-Flash formats.