I have Surround Sound set up and it works. When it's on the TV, DVD etc. sound is great, but as soon as the Wii is turned on or you play Guitar Hero or press a channel or navigate around in the Wii settings and menu you hear a high pitch noise/hiss sound at the end of loud sounds. It's like the volume is too loud. The sound you hear is like ringing in your ears, but in the background of the music and at the end of loud sounds. Any reason as to why? It never used to do that.