Is the Oppo your only source? If so, plug it directly into the power amp and use the remote controlled variable output built into the Oppo. I'm currently using my EVS Level 2 Mod'd Oppo 970 this way. Works just fine, except some of the volume steps are a bit too big. I sometimes have to choose between a bit too loud and a bit too soft....
Enjoy,
TIC
Enjoy,
TIC