Realtek HD Audio Manager
I do not know how many of you have notes, but after installing Realtek HD Audio Manager the volume got lower, and the audio quality as well.
Sounds like a difference between driver versions. Upgrade or downgrade to a different version and see what happens.
I see this all the time with Realtek and Windows 7.
Google is your Friend
Thanks Dogg. I have just went back to the default Win 7 driver.