I have a Pioneer Elite VSX-53TX receiver with Harman Kardon surround speakers. It all works well except once in a while the sound changes suddenly to VERY LOUD static noise. I have to turn off the receiver and it goes back to normal when I turn it back on. It probably happened only 3 times in the last month but, besides the fact that it scares the hell out of me every time, I think the neighbors don't like it either. Any idea? Thank you.