I was wondering if anyone else has experienced a popping or clicking noise in their speakers with digital sources on their 990. I notice it when I change channels on digital or HD TV. I notice it when I turn on xbox 360, or the dvd player. It will also make the noise for no reason, meaning while I'm watching a show in HD or playing a game on Xbox (and not actually changing the source). It doesn't seem to matter whether it's a coax or optical source. I haven't noticed it while watching a movie, only when changing the source to the dvd player. It's not a loud noise, just a click or small pop in the speakers.