Are you using any 32 bit plug-ins in the project you are working on?  Sometimes those prevent Sonar from closing properly.

I am probably using a 32 bit plugin here and there - but I was before I upgraded to the latest Platinum version and Windows 10 got updated.   But maybe the updates do not like the 32 bit plugs?

rolled back driver and firmware on Lynx AES16e and problem solved.
THANKS.

Hi deswind. Just curious. Do lynx have certified win10 drivers for the interface?
I have the same problem with my Roland VS system but I am pretty sure it's due to the drivers not officially being win10 supported. At least the problem started with win10.

I do not know if they are windows 10 certified, but I have been using windows 10 for a couple of years, and it was only the last several weeks that I had any problem.  I still cannot figure out why 256 sounds better than 512 on the asio latency.  Makes no sense to me.  And several weeks ago, I could go to 1024 without an issue.  Now it just likes 256.