Homedics SS-2000 Nature Sound Machine The new Homedics SS-2000 replaces the previous SS-200 model that was one of the most popular white noise machines on the market. the new model looks completely different but offers the same features. The Homedics SS-2000 has six digitally recorded sounds (Rain Forest, Ocean, Rain, Summer Night, Waterfall and Heartbeat) and a timer to turn the unit off after a pre-set length of time.