[COLOR=navy] When I listen to loud music for a long period of time, all of a sudden it sounds like someone turned a tone control all the way down on an old radio. All the highs just dissappear . When I turn the volume low it goes back to normal but when I raise the volume again, the same thing happens. It's like something is getting exhausted or something. I am using 2 ch mode with subwoofer. I'm running a Sony STR-DE585 reciever and Qest Q610's as mains. What's going on here? Is it the reciever or the speakers? How should I go about determening what is going wrong here? Maybe get another set of speakers and play those loud for a while and see what happens? Anyone have this experience before, or find a problem with the equipment..Anyone know what could be causing the problem? All help appreciated. Thanks in advance