in fact my office oso got weird things happen. my office is
divided into sections of cubicles. cos the cubicle panels are high
we cannot see one section from the other although they are all very
close to one another. and our doors are secure locked, activate by
access cards. when activated the door will emit a beep sound tt is
quite loud.
in the mornings or evenings when i am alone in the office, i can
always hear the mouse being clicked, the keyboard being typed at
the other sections. and from time to time, can hear the door being
activated although there is no one around or outside the office to
activate it. 
