I have 5 external hard drives (ranging from 1TB-3TB) and want to connect them all to an external USB hub. I have purchased a 7 port USB 3.0 hub with its own power source, but I am unable to get a stable connection of all hard drives, at the same time. All these drives have their own power source, but sometimes all 5 drives connect.. sometimes only 2 or 3, It's never consistant. Do I need a specific USB hub to make sure I have a stable connection for all my drives all the time ?