State Of Drones Not Restored After Opening
Condition
After opening in your DAW a project with Drones or MIDI Drones in it and then opening the associated arrangement in Synfire, the rack modules on the Sounds page are not restored to the state that was present when the arrangement was last saved.
Synfire shows a warning message that some sounds could not be restored when the arrangement is opened.
Cause
Your DAW might not have loaded the Drone plug-ins, or not early enough.
Remedy
Check the project settings in your DAW and make sure all plug-ins are
always loaded, whether the DAW thinks they are currently needed or
not.