Found the cause. The problem is caused by syndaemon running in background. Running "killall syndaemon" in the terminal restores normal mouse behavior. Unchecking "disable while typing" option in Mouse settings, apparently, does not shut down syndaemon nor prevent it from starting on the next reboot.
-- You received this bug notification because you are a member of Ubuntu-X, which is subscribed to xserver-xorg-input-evdev in ubuntu. https://bugs.launchpad.net/bugs/503041 Title: Mouse lags while moving it and clicking any keys _______________________________________________ Mailing list: https://launchpad.net/~ubuntu-x-swat Post to : ubuntu-x-swat@lists.launchpad.net Unsubscribe : https://launchpad.net/~ubuntu-x-swat More help : https://help.launchpad.net/ListHelp