FRA analysis

hello again,

we made a FRA for a system (attached picture) with enforced displacement of 1mm. The first plot shows the displacement of the mass without damping. The results are the same as we expected. The second plot shows the results for the same system with damping. we did not expect these results and can not understand them. we expected the maximum displacement at the eigenfrequency. is the second plot right and how can we understand it?

Thanks

We uploaded our model to your dropbox (LTC_FRA)