shutdownReason : ConfigurationChange, but only static files changed?

I'm on IIS 7.5 and ASP.NET 4 with latest official updates. I'm logging all application shutdown reasons. All is working ok, but since a week strange shutdown reasons are logged.

This now happens when static files are updated on the server. Example log:

shutDownMessage:

Change Notification for critical directories.  bin dir change or directory rename
HostingEnvironment initiated shutdown 
HostingEnvironment caused shutdown  
Change Notification for critical directories.  bin dir change or directory rename  
Change Notification for critical directories.  bin dir change or directory rename
... (50 lines !) 
Change in X:\IISTemp\ASPNET4Compilation\root\c6474edd\e8b7124f\hash\hash.web
Change Notification for critical directories.  bin dir change or directory rename  
Change Notification for critical directories.  bin dir change or directory rename  
... (20x !) 
CONFIG change  
CONFIG change  
CONFIG change

shutdownReason: BinDirChangeOrDirectoryRename

shutDownStack:

at System.Environment.GetStackTrace(Exception e, Boolean needFileInfo)  
at System.Environment.get_StackTrace()  
at System.Web.Hosting.HostingEnvironment.InitiateShutdownInternal()
at System.Web.HttpRuntime.ShutdownAppDomain(String stackTrace)  
at System.Web.HttpRuntime.OnCriticalDirectoryChange(Object sender, FileChangeEvent e)  
at System.Web.FileChangesMonitor.OnCriticaldirChange(Object sender, FileChangeEvent e)  
at System.Web.DirectoryMonitor.FireNotifications()
at System.Web.Util.WorkItem.CallCallbackWithAssert(WorkItemCallback callback)  
at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean ignoreSyncCtx)  
at System.Threading.QueueUserWorkItemCallback.System.Threading.IThreadPoolWorkItem.ExecuteWorkItem()
at System.Threading.ThreadPoolWorkQueue.Dispatch()  
at System.Threading._ThreadPoolWaitCallback.Per开发者_如何学CformWaitCallback()

Any idea ?

The problem has been fixed by updating time sync settings.