logic pro 11 Crash When Quitting Logic Pro

Logic Pro 11 Cashes when I quit and always right at the very moment when one would expect it to finish closing. I have been through the process of deleting preference files and the logic App and reinstalling Logic, 3rd Party Plugins and reinstalling MacOS (but not a clean install). Arturia have given me a lot of support because initially it looked like one of their plugins was the culprit but now I don't know that it is.

I am not losing work and the project files seem to be intact as they open again later without any issues but it's very annoying and I would like some help if anyone can.

I have already tried many remedies suggested by the support team at Arturia and I provided Apple with some reports etc some time ago but not holding my breath for any feedback. I feel it might be some considerable time before a remedy is made available even if it is a problem with Logic Pro 11. However, at the same time if there is something that I can do to fix the problem that would be great. After everything I have tried including reinstalling Plugins and apps, MacOS (not a clean install) I would like to do that. If I have to reinstall my operating system so be it but I don't want to try that unless it is necessary.