"infinite loop" -
did you ever figure out what was causing the hissing noise from your sony dav-fc8 system? i am also experiencing the same problem with mine.
to all other readers -
my system has the same squeel from mostly the center speaker while only on video1, video2 and the stereo tuner, but not on dvd mode. i unplug all cables including the video and fm/am antenna. when i reconnect the cables 1 by 1, the squeel increases slightly until i finally plug in the center speaker which greatly increases the squeel. also, the squeel grows louder when the volume is increased.
could this be caused by bad, weak, or dirty power coming from the ac electrical outlet in the wall of my hous