Plugins not working in Aux/Send Buses

Hey all, anybody having trouble using plugins on a bus/aux track in Logic? Trying to use an effect bus and send individual tracks to it and when I place a plugin in the aux track, the plugin window opens up and is greyed out; I can't adjust any knobs or parameters inside of the plugin. It seems like I have some kind of weird setting activated and I can't figure out how to undo this. Happens for both built in Logic plugins and third party.

Mac OS is Big Sur 11.7.10, Logic version 10.4.1

Any help is greatly appreciated.