Hi everybody!

I have this problem. During 2 years i used a xbmc mediacenter system with ubuntu 11.04 64bit. My mediacenter has an Asus Xonar D1 audio card connected to a homemade amplifier. Near the ubuntu os i have installed windows 7 to see the blu-ray movies.
Two days ago i have decided to upgrade my system to ubuntu 12.10. Then to make evething better i formated the ubuntu partition to a new one. I installed everything and all works fine like before except the sound card.
On the 5.1 system i hear only the two rear r/l, the center and the sobwoofer, but not the two front r/l.
I tried to solve the problem changing the /etc/pulse/daemon.conf, raising the volume on alsamixer and following this guide:


But nothing, the two front r/l don't want to work!
I want to point out that on windows partition all works fine.
Please help me!!!