Resolution
In order to bypass or stop Message Waiting Indicator (MWI) Resynchronization on the Cisco Unity server, complete these steps:
Choose Tools Depot > Switch Integration Tools, and open Telephony Integration Manager.
Expand Cisco CallManager.
Click Properties.
Locate the MWI Synchronization section.
Uncheck the Resynchronize At check box.
Refer to Message Waiting Indicators (MWIs) for more information.