I have noticed that my rear front case header USB is allot faster then my rear motherboard I/O. For example, if I plugin my Logitech unifying receiver into the front I/O, I can use my mouse across my room. If I plug it into any of the rear motherboard I/O, it stops properly working a couple feet away. I have a similar problem with my Wireless G933 Logitech Gaming Headset. I have an older motherboard, its an ASRock 970 Extreme4.