usb 3.0 not seeing my usb 2.0 device on new macbook pro

I bought a new Macbook Pro, and my audio mixer device from Tascam does not work with it. It works great with my old Macbook pro, and I made sure they both have the same OS 10.9.4. I have the most recent driver installed as well. The device specifications say usb 2.0. It is an older device, but it works great on my older Macbook Pro with usb 2.0. Extremely frustrating, I need this to work!!!