If you downgrade to Flash 10.3, does it still happen? Flash 11.3 doesn't load video in Firefox (ignore the title).

Or disable Flash Hardware acceleration.

I have not tried to go back to an older version of flash: I was not sure I could do this without exposing my computer to the vulnerabilities that the security patches in new releases fix.

If the reset and driver update does not fix the issue, maybe I should try uninstalling and clean installing Firefox.

( I do not have the other serious problems that people seem to be having with flash not loading in the latest FF. I mean I can still watch Youtube, hulu, etc.)

Thanks again.

Flash has been causing alot of weird issues lately. Using Flash 10.3 will keep you up to date with all the security fixes in 11.3, so you are safe to downgrade. Especially since you aren't having issues, if you see the issue still happens with 10.3, go ahead and upgrade back to 11.3

Ok, will try the solutions in that order and will report back.

But I think it is flash in Firefox, as this problem is not there with my IE9.

(While the IE9 32-bit has no glitches with flash, IE9 64-bit has one tiny annoyance: Watching a Youtube clip on the full screen mode shows the browser's top and bottom edges; and mousing over the player controls makes them jitter. For some reason IE9 64-bit uses the now reviled HTML5 player though I did not give permission to join the beta testing.)

Moe than you probably wanted to know.

Did you try to "disable the hardware acceleration" in the Flash Player.

• http://helpx.adobe.com/flash-player/kb/video-playback-issues.html

See also:

• https://support.mozilla.org/kb/keep-flash-up-to-date-and-troubleshoot-problems

Flash "Display settings" window:

• http://www.macromedia.com/support/documentation/en/flashplayer/help/help01.html

Just so you know, the version of Flash in Firefox is totally differen than the version in IE (and chrome), so the absence of a problem in one browser doesn't mean it isn't a Flash issue.

Sorry, it took me a while to give feedback for the suggestions you have given here.

(Please refer to sidebar on the original post for system details.)

I have reset the profile and updated the Nvidia driver. The version of FF is 14.0.1. But it still scrambles the pictures.

On top of scrambling the flash content when scrolling, it has additional problems:

As you can see from the attached image, another tab's content is showing on the youtube flash player. This happens when I have paused the video even for a short time.

I have a suspicion that the combination of Flash and Firefox does some weird things to graphic processing and memory.

(I realize that IE implements Flash differently, but they seem to have this right.)

I might just have to say goodbye to Firefox for a while.

Thanks.