When facing issues along with Standalone instruments/plugins or FXs plugins, it is a good practice to start by attempting deleting preferences files in case such would help resolving them.
-Such can be easily done from the Arturia Software Center as explained in the other following FAQ Article:
Arturia Software Center (ASC) - How to clean Instruments & FXs preferences
-However, in some situations you may prefer doing so manually as explained in the video below:
Note
Keep in mind that doing so will delete the following settings:
-Midi controller selection and Midi Mapping
-Audio device selection and Audio settings (Sample Rate & Buffer size)
-Tempo setting (Standalone only)
-Last selected preset
-GUI size and Skin settings
-Startup Tutorials (if on or off)
If you created any custom MIDI mappings for instruments/effects, make sure to back them up with the "Preferences" -> "MIDI" -> "MIDI Config" -> "Export current preset" function located in the side-panel of the instrument.
Please find below detailed steps depending on your Operating System.
-Go to the following folder:
Note
-Delete all the files contained inside the folder and reopen the instrument to confirm if issues are now resolved.