Hi Dolf
Try this.........it may or may not help.......
On a Computer connected to your local network (which I assume the Sooloos is connected to as well)
Open a Browser..........in the Address Bar, enter the IP Address of the Sooloos Core, which I assume is your Control 15
This is likely to be something like "192.168.1.xxx" or perhaps "10.0.1.xxx"
After you enter that address, the Browser will return an Interface into your entire Sooloos System
Near the top of the page, you'll see two boxes........"Play" and "Settings".......Click on "Settings"
The screen will then show you a list of the Sooloos Zones..........look for whatever you may have called your ID40 Zone..........and to the right of that, you'll see a box again called "Settings"............click that box
A Dialog Box will appear with the Zone Name.........underneath that, you'll see "Volume Leveling" with Tick Boxes for "Off"....."Song"........."Album"
Click on the Tick Box for "Song"..............now click on the top right hand corner of the Dialog box to close...........reopen the Dialog box again to make sure that it has retained your setting
Now try replaying a "quiet" song followed by a known "loud" song and see if the 861/ID40 reacts properly
Hope that helps
Ronnie