We have a 3 yr old ge refrigerator, model gth18hcb3rww. In the past month a loud motor noise began. It is not constant. The refrigerator is working properly. Sometimes I can unplug the frig and it will go back to a low motor noise. And when this works, I hear a couple of clicking sounds, like an ice cube tray melting crackle. And sometimes unplugging and replugging doesn't work and noise continues until motor cycle is over. Any ideas what this might be?