Dial values from parameters

Hi,


I have created two drop down list parameters (values from a MDX query).
The issue is that whenever the parameter value is selected, the dial values change.
with a bar chart all is ok (listeners => val_xx; parameters => Arg val_xx Value val_xx; ), bat the dial don't refresh.
In dial there isn't option: parameters ..

How can i refresh the dial?
How can i reload the query (MDX query) to dial refresh?
..


Thanks for your help.
Ettore