I have this problem with my system, initially I thought it might have been KDE as I was using Gnome in 10.04. I later found that the same thing occurred when using fluxbox so it obviously wasn't KDE related. http://ubuntuforums.org/showthread.php?p=10032443 For me I found it happened more when I had a virtual machine running (but it did still occur when no VM was running.)
I have this problem with my system, initially I thought it might have been KDE as I was using Gnome in 10.04. I later found that the same thing occurred when using fluxbox so it obviously wasn't KDE related. http:// ubuntuforums. org/showthread. php?p=10032443 For me I found it happened more when I had a virtual machine running (but it did still occur when no VM was running.)