I'm getting:

--- Start Exception Stack ---
System.NullReferenceException: Object reference not set to an instance of an object.
at prairieFyre.Routing.Mitel.MitelBaseDevice.ProcessMiTAIEvent(BaseCallControlEvent callControlEvent)
--- End Exception Stack ---

in my RoutingInboundService.log for every one of my phone calls. Not sure where to start to fix the problem? Could someone give me some background?

Thanks