I have some Cyber Accoustic (CA2002) PC speakers connected to my laptop. Periodically, I here some type higher pitched static sound coming through the speakers. It starts with a slow frequency then gets very fast. It last about 5 seconds and sometimes longer. I have a desktop PC under my desk with speakers also. I use to hear the same sound from them but not as loud. Sometimes I hear this sound through the headphones in my digital piano across the room. Is there a way to eliminate it?