Would be interesting what your systems have in common. The most suspicious ones are gtk+ version and window-manager in use.
Do you both use "compiz" and gtk+ 3.10.8 on Ubuntu/14.04?
Reproducing it with another window-manager might suggest it being a problem of plank.
As a note, clicking on the dock should not make it hide in any case. This is only suppose to happen when the mouse cursor leaves the dock.
Would be interesting what your systems have in common. The most suspicious ones are gtk+ version and window-manager in use.
Do you both use "compiz" and gtk+ 3.10.8 on Ubuntu/14.04?
Reproducing it with another window-manager might suggest it being a problem of plank.
As a note, clicking on the dock should not make it hide in any case. This is only suppose to happen when the mouse cursor leaves the dock.