The sound of the compressor turning on and off bothers me. How can I stop that?

The compressor is designed to turn on whenever the temperature reaches two degrees above the preset temperature; and turn off once the temperature drops two degrees below the preset. It cycles like this, back and forth, maintaining the set temperature for your room. The only way to avoid this cycle is to set the unit to a much lower temperature – and that will keep the compressor on for longer.