Insufficient mains filtering in the unit, or the power wiring is common to your room, and not a separate connection back to the distribution board. If you are sharing the same socket outlet, most likely, then you need to install a mains filter in the line to the AC unit, rated for it's run current, and another to the equipment in your room. Otherwise a separate cable to the distribution board, and a separate breaker for it, still with a mains filter to the equipment in your room.