Yamaha DTXpress/DTXplorer/DTXtreme

Hi,

A few days ago I received my DTXpress. One of the main reasons why I 
bought it was the fact my neighbors were complaining about excessive 
volume levels. I was absolutely sure this will be the solution to the 
problem.
However, it turns out I was wrong, one of my neighbors who lives 
right above my apartment is still complaining - I personally think 
that the reason could only be the kick pad.
How can I make it sound quieter? Should I replace the pedal beater? 
Should I place the DTXpress over some stage? Should I cover the pad 
with something?

Please help me, especially if you have any experience with such a 
problem - this neighbor is fuckin' crazy and he threatens that he 
won't let us sleep at night (he's cleaning his house between 
1:00-2:00 AM).

Thanks,
Nir.

P.s: if you could E-mail me an answer it will be more comfortable.