Virtualization : Time Service Syncronization
For virtual machines that are configured as domain controllers, disable time synchronization with the host through Integration Services. Instead, accept the default Windows Time service (W32time) domain hierarchy time synchronization.
Host time synchronization makes it possible for guest operating systems to synchronize their system clocks with the system clock of the host operating system. Because domain controllers have their own time synchronization mechanism, host time synchronization must be disabled on virtual machines that are configured as domain controllers. If domain controllers synchronize time from their own source and also synchronize time from the host, the domain controller time can change frequently. Because many domain controller tasks are tied to the system time, a jump in the system time could cause lingering objects to be left in the directory and replication to be stopped.
You can disable host time synchronization in the virtual machine settings in the Integration Services section of the Hyper-V Manager by clearing the Time Synchronization check box.