My Book 6 TB driver seems to go into “Unknown USB Device (Link in Compliance Mode)” and I think it is after waking up from power save state. It maybe timing out on the driver and the OS puts it into “Compliance Mode”. I have had this problem with Graphics drivers too, the graphic driver times out and generates an error. The Graphics Drivers can be fixed by adjusting the Timeout Detection and Recovery (TDR) Registry Keys. Is there something similar for hard drives?