I just got a Bookeen Cybook and keeps getting more and more books into it days after day

. So I find it quite inconvenient to have to plug the Cybook to PC through a cable because I think it's likely to wear out the plug in Cybook.
So I wonder if it's able to
sync the books to the SD card by using SD card reader, instead through the Cybook because I also have a SD card reader on my PC. However, whenever I try to sync the books to the SD card, which the PC recognised as Removable Disk, it continually stops and shows some errors.
I can easily copy the files but I want my Cybook and PC contents synced. Anyone help please.