Not only that but the entire thing is trial and error between your individual computer, your controllers, the actual Hubs themselves. Ive bought powered Hubs that windows doesnt even recognize even tho I have the same kind of Hub that it does. Even when I connect the one Hub to the same port the other one is recognized on windows still doesnt see it. Ive been thru this on 4 different boxes, this Digital Storm one has actually been easier then most but even with it Ive had issues.
Anytime you connect anything to anything you have a potential weak link in the chain. That and Ive found USB to be persnickity at best which is why I went FW-800 for all my video backup. Even then heres a list of USB devices I have on this box, a Saitek throttle/stick, a rudder, a mouse, a wireless mouse, a keyboard, a G13 pad controller, 2 printers, a fit bit, an entire racing setup with throttle-brakes and whoknowswhatelse, a Game head set, a TrackIR. And Im probably forgetting a few things. Windows and USB says there shouldnt be a problem but there is and its with windows assigning IDs to the devices and the ports/hubs reading them right.
There is no science to it, its trial and error. Saitek is a dream unit now compared to those first SST writes. What a disaster those were. I hope our friend stays with it. To be honest it sounds like a power issue. I have a Saitek throttle whose MFD light often goes out and I have to reconnect it to the powered Hub for it to turn on again.