Ok, this makes sense. Because we are now responding to these messages with a different thread all the available threads are being used up. How many BACnet data points do you have and why type of hardware are you running on?
We've made the thread pools adjustable in the next version of Mango 2.6 but here are some temporary replacement files to increate your threads:
This will increase your high priority threads from 100 to 1000.
Place the classes folder into overrides/classes, ensure you don’t overwrite anything that is already there
copy the properties about the configurable thread pools from the env.properties file included
— Mango needs to be shutdown at this point —
Remove ma-priv-1.2.4.jar and move the ma-priv-1.2.5.jar into lib
Start Mango back up and see if this problem is resolved.