USB Interface Not Staying Connected

I have an Akai EIE Pro USB interface that I've been running into to my mid-2011 iMac with no problems at all. Just recently however when I connect the interface it stays connected for about 20 seconds then my computer acts like it's not connected anymore. If I turn off the interface and turn it back on it will just do the same thing. I have tried a new USB cable, and I know its not the interface because I have tried it with different computers and it worked fine. I have also tried updating the drivers and that didn't work.

Like I said earlier my computer is a mid-2011 iMac i5 with the latest OS.