System Center Endpoint protection

Since the 20th of June we have been seeing Windows 7 machines (not everyday but most) have the  Antimalware service stopped and we get the following log entry with different files listed under Resource:

Log Name:      System
Source:        Microsoft Antimalware
Date:          6/29/2015 11:58:31 AM
Event ID:      5008

Microsoft Antimalware engine has been terminated due to an unexpected error.
  Failure Type: Hang
  Exception code:
  Resource: file:C:\Windows\winsxs\x86_microsoft-windows-minkernelapinamespace_31bf3856ad364e35_6.1.7601.18015_none_0cba39e5da114d7c\api-ms-win-core-memory-l1-1-0.dll

or

  Resource: file:C:\Windows\winsxs\x86_microsoft-windows-minkernelapinamespace_31bf3856ad364e35_6.1.7601.18015_none_0cba39e5da114d7c\api-ms-win-core-rtlsupport-l1-1-0.dll

or

Resource: file:C:\Windows\winsxs\x86_microsoft-windows-minkernelapinamespace_31bf3856ad364e35_6.1.7601.18015_none_0cba39e5da114d7c\api-ms-win-core-processenvironment-l1-1-0.dll

or

file:C:\Windows\winsxs\x86_microsoft-windows-minkernelapinamespace_31bf3856ad364e35_6.1.7601.18015_none_0cba39e5da114d7c\api-ms-win-core-sysinfo-l1-1-0.dl

It looks like the service hangs between 11:30 AM and 12:30 PM

Can't find any kind of Malware on them. Does anyone know what would suddenly cause the antimalware service to hang.

You really should open a case with Microsoft customer support service ASAP.