After applying NP template - how to get rid of unused mixer lanes?

I started with the wind band template that ships with dorico and applied the NP playback template later on.
Now, how do I get rid of all the mixer lanes that are not needed anymore?

NP plays back on just one of them (as was expected), but there are about 30 lanes I don’t need :wink:

You could hide unused channels in the Mixer? in the toolbar, deactivate Unused.