I've had a Dell E521 desktop for over a year. I've had absolutely no problems even with Windows Vista. I customized the audio at the time and went with the A525 dell speakers plus subwoofer. The High Definition audio was perfect and worked fine until this week. I noticed the green light on my subwoofer was out. There was still some bass coming from the subwoofer but it wasn't as powerful. I tried reinstalling the audio drivers, adjusting the Sigma tel high definition audio CODEC settings, unplugging the ac adapter and trying another outlet and none of it worked. I called Dell tech support, they wanted me to repeat these steps, obviously it still didn't work. They overnighted me another set of speakers with subwoofer. I just hooked them up and i'm having the same problem. There is some bass but the green light does not come on. It's worked fine for over a year so i'm not sure what exactly happened. Any help is appreciated.