I have a BDP-93 and I'm pretty sure the volume control is analog but it has a digital control (probably an e-pot). Also, a digital volume control, if it's controlling the reference voltage to the DAC, reduces the resolution of the bit depth, it does not reduce the sampling rate.
There is a Wiki for OPPO products, wiki.oppodigital.com.
There is a Wiki for OPPO products, wiki.oppodigital.com.