I am running 3 x 2 terabyte Seagate Barracuda external powered hard drives and a variety of flash drives through a externally powered usb hub which is then plugged into the BDP-1. I found the 64mb cache hard drives don't work, so I am using the 32mb cache hard drives instead (put all the 64mb cache drives into my pc so no loss incurred.) Maybe its just a hard drive enclosure issue (using "no name" brand generic enclosures). It all works, so I am not phased.