Microsoft SCCM has a Health Agent Task scheduled to run over night. The task does not support WMI 3.0. WMI 3.0 is incorporated in Veeam Backup & Replication as a dependency. When the Health Agent clears the WMI repository, it kills Veeam services in the process. You might see other WMI errors in the event logs, or a message about an SMS Agent starting shortly before.
Please see the following Microsoft KB article http://support.microsoft.com/kb/2796086 for instructions on how to prevent the issue. Alternatively, open the task scheduler, expand Task Scheduler Library > Microsoft > Configuration Manager and disable the task.