This might be a bit of an unusual question, but I used to have windows 8.1 for the past three years on an HP Envy dv7 Laptop (it came preinstalled). Playing music in Windows Media Player used to work fine.
Recently, my System Drive got smoked, so I installed a new SSD and a copy of Windows 7 Ultimate on it. Now, when I play music, it sounds like someone is rattling garbage cans in front of my ears - ok, not that bad. But there was a considerable drop in sound quality. I have confirmed that it is NOT related to the equalizer/SRS WOW effect settings in WMP.
My best guess would be that my old installation came with some sort of audio driver or virtual audio device. However, that's confusing, because I have ever been (and still am) using the audio device from my Monitor via HDMI (a Samsung SyncMaster XL2370, which installs an audio device called "SyncMaster (Intel (R) Display Audio)", like this). So in terms of audio quality, there should be no difference, because the Monitor should receive a digital signal, and as such, I'm wondering where in the chain the audio gets messed up?
On my old installation, I used to have something called "Realtek High Definition Audio something", and in device manager, i can still find that. However, it seems to also be unrelated, as deactivating it via device manager doesn't change/make my audio go away. I can still listen to music, and it still sounds bad.