USB Device Disabled

I just purchased a USB3-HUB7-81X and a USB3-3900DHE in order to run a second external monitor on my Macbook Pro. I installed them both on Friday and got everything working fine. Today I’m getting a USB Devices Disabled message and the second screen works intermittently. When I attach the USB3-3900DHE directly yo the MBP it works fine and I get no error message. But anytime I attach the HUB7 without anything else attached, I still get the message. I’ve tried both USB ports and even plugged in the HUB7 directly into the wall, not through the power strip it was plugged in to. It seems like the HUB7 is faulty, but wanted to check here first. !](https://d2r1vs3d9006ap.cloudfront.net/s3_images/1147423/ScreenShot2015-01-26at10.29.27AM_inline.png?1422297789)](https://d2r1vs3d9006ap.cloudfront.net/s3_images/1147423/ScreenShot2015-01-26at10.29.27AM.png?1422297789)