CRM Async Service Error Message: (MSCRMAsyncService)

Hi 

Please assist me with an error I am getting on my CRM server. The error is not specific enough, even when I enable tracing I don't get anything more specific.

failed while monitoring asynchronous operations queue. Exception: System.NullReferenceException: Object reference not set to an instance of an object.

Please assist. Its CRM 2013 deployment.