Big differences volume level aircraft sounds - any solutions?

Hi all,

Flying with different aircraft, I notice there is a huge difference in volumelevel of the default aircraft sounds and several addons (commercial aircraftsound addons and freeware sounds that come with planes).

Has anybody found a practical way to make these volumes a bit more equal without loosing the meant to be volume differences ?

Any suggestions are welcome too, ofcourse 8)

Greetings,
Bram Stikkel