What is the "BE Engine"?
Likely something that upsamples like HQplayer. But if the source is already DSD256, the up sampling isn't required. Another option is offline SDM/SRC. Bottom line is, anyone looking for the best sound in digital period, should take this SD card transport seriously. Either that or find a transport/external Ethernet renderer like the Sonore Signature Rendu, that can output pure I2S/DSD over HDMI.
Seriously you guys are throwing your hard earned money in the wind just to get worse sound by not taking advantage of these protocols.