I have an older Yamaha Receiver, (4) Gallo Adiva speakers and an inexpensive subwoofer. I have it hooked up to my Panasonic Plasma HDTV, digital audio out of the TV---digital into the Yamaha Receiver. I have the system wired in stereo...two of the speakers are hooked up left / right in front of the TV, and two of the speakers are back by me behind the couch left / right. I've been using this equipment in this configuration for a year and it's been perfect. All of a sudden a day or two ago, I turned on the Yamaha Receiver and when playing the TV, I feel an uncomfortable pressure on my ear drums that was never there before. When I pause the TV, it slowly goes away. The pressure is similar to, but not exactly, like that you might feel when using noise-cancelling headsets...but alot worse and causes headaches. The actual sound of the stereo is pretty much what it's always been,...perhaps the lows are little emphasized, but not very different at all. I have no idea where this problem came from or even where to look to solve it. I've been using the TV with it's own built in speakers for the last day or two to avoid the pressure on my ears. Any suggestions on where to look for the problem would be appreciated.