Adjusting the Idle factor will adjust the descent profile, not sure which way though. An average managed descent with the a/c on profile will descend with power on (approx 44.5 N1) just in case you need to use engine anti ice or environmental conditions change. If you get high, the speed increases to the edge of the 20kts bracket and then it reduces power.
Next time you go flying, in the above mentioned conditions, switch on engine anti ice and take a look at the N1, it should say Idle or very close.
I would be very careful and not touch this setting but maybe seek guidance from your tech pilot.
Rgds
MF
Last edited by Man Flex 37.5; 23rd Aug 2008 at 19:53.