I'm running 7100 with Logitech Z-2300 speakers and I noticed recently the subwoofer is producing little or no sound. I unplugged my laptop and plugged my iphone into the speakers and verified that the subwoofer does work with a different input. I then hooked my laptop up to my home theater system (which has an Infinity 300 watt sub) and got no bass output there either. So basically, the problem is in Windows. I assume a driver is at fault but I can't seem to figure it out. Is anyone else having a similar problem with bass?