Is your USB-HUB powered from external power adapter? URG-04LX-UG01 seems to consume 2,5W/5V=0,5A. This is limit for USB. Laptop USB ports are not so powerful and if device consumes a little bit more than max, then they just cut the power.
Update
The device is USB 2.0 Full Speed. I've seen USB controller, that had problems with USB 1.0 or USB 2.0 devices. Hub presents itself as USB 2.0 High Speed and handles USB 2.0 Full Speed transparently for the Laptops USB controller. Do you have another Laptop/PC to check this?