He might be thinking about unwanted/competing codecs, since they effectively "bid" to play an audio stream, and Windows will never stop you adding another codec. Drivers, on the other hand, are pretty good at not doubling up since that's detected during installation.
The piccy you posted earlier with the Altec speakers shows you have nothing plugged in, and the motherboard doesn't have a SPDIF digital audio connector, which I suspect is incorrect. I'm beginning to suspect a hardware problem, but your description of the bar bobbing up and down suggests both the hardware and drivers are fine. Er, I suppose the speakers are known to work??