I've never posted here before but I've been unable to find any solutions online so I thought I would ask.

I have a desktop and a laptop, both running ubuntu 14.10. I first noticed that youtube videos weren't playing in firefox on my desktop a couple of days ago. Instead of playing, I'd get the message "an error occured, please try again later." Even though I had the flash plugin for firefox and chrome installed from the ubuntu software center, flash had stopped working in firefox. However, it was still working in chromium. Today I only have access to my laptop, but I've just noticed that the flash plugin has stopped working in firefox. In Chromium, youtube videos will play, but the shockwave flash plugin for games has stopped working. I get an error message that shockwave flash has stopped responding.

I'll also mention, since I'm unsure if it's related, that up until a day or so ago I was using a custom theme on my ubuntu desktop (numix), but after a software update I lost the ability to change the theme and my desktop had reverted back to the default theme (switching to gnome from unity allowed me to change the theme again, but in unity I was stuck with the default theme). It was at this time that I noticed flash had stopped working.

I have tried updating both web browsers and reinstalling the flash plugin through the software center. I also tried installing flash directly from the flash website using the downloadable tar.gz file, but I'm not sure if I installed it correctly since I was trying to follow instructions I had found online on how to install a tar.gz.

Does anybody have any ideas as to how I can fix these issues? I've been unable to find any threads made by people experiencing the same problem, which is what I usually look to for answers.