As of firmware version BDP10x-50-0422, released on 03/05/2013, the BDP-10xAU series of players is capable of playing DSD files via USB hard drives, USB thumb drives, and SMB.
The files will need to use either the DFF or DSF file extension, and the supported sampling rate is 2.8224 MHz (DSD64). Both stereo and multi-channel files are supported.
To play DSD files in DFF or DSF format, simply copy the files to a USB hard drive or thumb drive, plug in the drive to one of the USB ports on the BDP-103AU/103D/105AU player, and browse for the file from the "Music" entry on the player's Home Menu. DSD files shared via SMB can be accessed from the "Network" entry on the player's Home Menu.