Ttry the fix noted at http://divyen.wordpress.com/2011/05/08/fixing-adobe-flash-firefox-plugin-crash-full-screen-ubuntu-11-04/
Bob
Running Ubuntu 11.04 on a P4 (Celeron actually) 2.93 with 1G ram. Biostar P4M90-M4 board (I was scavenging).
No matter what media player I use (Kaffeine, VLC or Gnome Movie Player) whenever I place the cursor anywhere on the frame of the media player interface and click a mouse button(lets say to expand to full screen or to drop the volume) the OS crashes. Don't have this problem on my Dell Inspiron 8500 laptop, just on the desktop!
Any ideas, similar issues, work arounds?
Thanks.

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