You mention the controller, but not what amps you are using. If the amps have their own gain settings, this could give WSDK some problems.
You should be able to play with the manual WSDK tuning features to reduce the gain and damping values. As I understand it, WSDK has a few options for tuning formats. Use what gets you close, then finish it off manually if need be.
I am not registered on the galil site, so cannot peek at the 1840 manual, but did see some on the WSDK tuning that you may already have access to.
Best of luck.