- The most probable reason for a slow exit is the activation of totem while also having render nodes in "Use" state but being offline. 

It happens because Mistika will try to connect on exit to free their frame servers, and if they are not available it will need to wait for a connection timeout

For example, it could happen if you configured totem in the past with a render node that is not available anymore (or if it changed its name or ip address)


- Go to Render->Totem settings wheel to see the "used" nodes, and deactivate any node that is not available

- Alternatively (if you do not need totem), deactivate mConfig->Totem->Use Totem

- Other potential solutions:  

Other potential causes are related to the activation in mConfig of other devices not available to the system, like color panels, remote streaming servers, unavailable disks or network drives, etc.