USB 3.0 ports on dock work at USB 2.0 speeds with my Venue Pro 11 5130

I tested the USB performance of my Venue Pro 11 5130 while docked into a K10A001 dock (all black, 3 USB 3.0 ports). While the tablet's own USB 3.0 port works as fast as it should (about 150MB/s with an external hard drive), the ports on the dock max out at 35-40MB/s, which is the USB 2.0 practical limit. I tried with a few different USB 3.0 drives and got the same result. I then ran Dell's diagnostic utility on the dock's  USB ports and it saw them as USB 2.0, even though they are labeled Super Speed and marketed as USB 3.

Dell, where's my speed? I paid for a USB3 dock.

Could this issue be specific to the 5130 model? Like, the higher ones work fine at 3.0 speeds with the dock and too few people use the 5130 with the dock to notice?