driveline vibration after clutch install

[shadow1]

I just replaced a my worn out OEM clutch and flywheel with an ACT 2100 clutch and XACT Streetlite flywheel. I now get driveline vibration when I decelerate in gear. Car drives and shifts fine otherwise. Acceleration is fine, even past 90 mph. The whole car seems to buzz. Is this expected with lightened flywheels?

 

[94awdcoupe]

Solid center clutches transmit noises to driveshaft.

 

[shadow1]

I know performance clutches and flywheels do sacrifice some driveability issues. I just want to make sure that other AWD DSM owners with ACT clutches have similar experiences. I'm paranoid that something might be wrong.