Hi!
As it is mentionned in the user manual, the ADI-2 DAC will detect the sample rate, no need to "change" it. The master clock is the BR player and the ADI-2 DAC adjusts its clock on it.
If you want to play your CD at the native 44.1 sample rate, the setting must be done in the BR player parameters.
I'm surprised than the BR player resamples the sound though. All the video files (DVD, BR) have samples @48Khz, but you should try to play a CD with it, I'm pretty sure the sample rate will be @44.1 for a CD.
ADI-2 DAC (with stock PSU) - Neumann KH 310 A monitors - Cheap USB and XLR cables