Cant figure out why flash is so broken on everything except IE

Question

The hardware with the issue is the acer 522 netbook, it has an amd c-50 apu that will decode 1080p no problem.
flash used to work great on firefox and chrome around the 11.3 era, I remember when amd had to issue a driver to enable the video accel but since ~11.7 firefox and chrome are dropping frames and eating tonnes of cpu cycles [on a netbook where flash has become too costly]. the solution seems to just use IE but it is terribly insecure and all my history is in firefox and chrome [which used to work].
Main issue is youtube. ff/chrome will drop frames at 480p and up while IE10 wont even sweat 1080p30. Even using the same version IE gets better results. Also this is true for windows 7 and 8.
all three are using the same version[chrome might not be] but are using different apis, pepper, netscape, active-x[off the top of my head] so I doubt the interface is the issue...anyone have any ideas?

Answer 1

Do you run any plugins such as Firebug? I have been trying to play a MP4 video that I uploaded to a website and was getting a lot of dropped frames in the Flash player during playback which made it unbearable to watch. I mainly use Firefox on my Macbook Pro i5 and happened to try it in Safari and the video played smoothly with no dropped frames.
I read somewhere that someone mentioned turning off Firebug which I happen to use in Firefox for development. Disabling Firebug immediately allowed the video to play correctly in Firefox once I did this. Perhaps if not Firebug, you have some other plugin that is causing the problem? You might want to try disabling all unecessary plugins in each browser to see if it works.