The system includes a digital cable box, sony surround sound receiver with DVD player and a wega 42"lcd.
The system is 2 years old and suddenly developed a high pitch background noise as the speakers play the sound. I have played a dvd and the system works fine. I have also exchanged the cable box and the replacement did not help. I have checked the wiring to the 6 speakers and have unplugged 1 at a time, they all produce a similar pitch. I moved 1 speaker 10' from the TV and still get the high pitch sound.
In search of a solution

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