logic pro plug-ins work on some tracks but not others

Hi there,

I'm new to Logic Pro X after having upgraded from GarageBand after getting to grips with that over a few months. Now I have this interesting issue with Logic's stock plug-ins that rears it ugly head now and then. 98% of the time when I add a native plug-in to a track it foes what you expect it to do. But sometimes the added plug in cannot be modified via its dedicated screen. The blue on light is on, but is not as blue as in other plug-ins that are fully functional. None of the menus work, and the plug-in can only be turned off via the audio effects slot. Even when I copy and paste another fully adjustable plug-in from another track the pated plug in takes on the same characteristics.

Here is a screenshot:

On, but not adjustable.

Am I doing something I'm not aware of, like disabling an option somewhere?

(2015 entry level 27" iMac, latest Logic Pro X version, latest public release of MacOS 14 (Mojave)

Cheers in advance,