I got a hifi DAC,it work perfectly at osmc.but when I try recalbox following this "create the file /etc/asound.conf",it can't work,it say read-system file,but I used the root to login from putty.pls help me,thanks a lot.

I follow this link
https://github.com/recalbox/recalbox-os/wiki/Audio-HiFiBerry-(EN)