My computer speakers been acting really strange the last 2 weeks, i havent changed the driver or anything but my computer has just stop detecting my audio device, it detects it for around 30 secs when you boot up the computer, but it disseapears after that. When i go to control panal, sounds and audio device it keeps saying "No audio device" and when i click on the volum control on the task bar it says " there are no active mixer devices available. to installl mixer devices, go to control panel, click printers and other hardware, and then click add hardware." so far i have tried uninstalling the driver and reinstalling, reinstalling window xp sp2 tried setting the bios and i have also ran virus, spyware, trojan and registry scans and they cant seem to detact a virus or anything. my computer runs on a pentium 4 asus VIA PT800 160gb sata HD radeon 9600 graphics card i have been using this computer for around 2 years now and this problem has never happened before. i have no idea how to fix it, the only sounds that it can play is system sounds and clips that you stream off the internet, i cant hear any sounds from movies that i have and media player cant play any sounds as well.