I would assume that the DR-1 would reset its digital volume control to max whenever it would be turned on and off. If you happen to have another transport/player arround that you could also plug into the DAC, or just another source, switch between and "see" if the volume out of the DR-1 is lower.
Ultimately you could contact CJ, they would be able to tell you. They have excellent customer service.
Ultimately you could contact CJ, they would be able to tell you. They have excellent customer service.