Line out volume adjustment in Wolfson WM8731 audio codec

Thanks, but I just used the wrong terminology. I meant to say "headphone volume", not line out volume. I know that the line out signals are unconnected and, in fact, the line out volume cannot even be altered (only muted or unmuted). I have fixed my original post.

I am actually using the headphone out signal and attempting to write to register# 2 (a.k.a. R2 or 0x02) in the codec. And it appears that the volume can only be set one time upon initial programming and then never again...