I have the 1616m version, and regardless on what version you have, i've read how sketchy the driver support is for Win7.
There are beta drivers for Win7 available on EMu's site but its not a sure guarantee on whether it will run properly. Some have reported only being able to record up to 48Khz.
For now I have stuck with using the unit on the 32-bit version since the drivers are stable.
I am in process of trying to test the card under Win7 64 so we will see.