It really helped me on my MSI Mainboard - had low sound before. My ALC888 is a realtek though - you own a nvidia.
Can you choose the oss mixer from the gnome applet? and adjust the levels there?
I know this is just a guess, probably not working - but there was a time in my linux audio history, where changing these levels made a higher output happen (Soundblaster Live years ago - alsa was just included into the kernel)
It really helped me on my MSI Mainboard - had low sound before. My ALC888 is a realtek though - you own a nvidia.
Can you choose the oss mixer from the gnome applet? and adjust the levels there?
I know this is just a guess, probably not working - but there was a time in my linux audio history, where changing these levels made a higher output happen (Soundblaster Live years ago - alsa was just included into the kernel)
Peter