I saw this recently, early windows XP games with better audio (although with a good soundcard) than most games made today.
Sure windows Vista killed accelerated audio, but recent attempts failed to resurrect it.
All AMD cards have a very good audio dsp that's unused, PS4 has the same tech, the Xbox one has a completely overpowered one (same performance as a single 360 CPU core).
I started hearing this after I installed a old 5.1 receiver that was in the attic with it's speakers, the difference is huge when you have good surround support.