Windows 2012 Domain Controller - DNS Event ID 4015

Having a peculiar issue with a Windows 2012 domain controller.  On 4/17/2013 at 8:06:58PM, Event Viewer logged an error 4015 under DNS Server.  The DNS-Server-Service lists this as the fault:
The DNS server has encountered a critical error from the Active Directory.  Check that AD is functioning properly.  The extended error debug information (which may be empty) is "".  The event data contains the error.

Here are the details:
- <Event xmlns="http://schemas.microsoft.com/win/2004/08/events/event">
- <System>
  <Provider Name="Microsoft-Windows-DNS-Server-Service" Guid="{71A551F5-C893-4849-886B-B5EC8502641E}" EventSourceName="DNS" />
  <EventID Qualifiers="49152">4015</EventID>
  <Version>0</Version>
  <Level>2</Level>
  <Task>0</Task>
  <Opcode>0</Opcode>
  <Keywords>0x80000000000000</Keywords>
  <TimeCreated SystemTime="2013-04-18T00:06:58.000000000Z" />
  <EventRecordID>404</EventRecordID>
  <Correlation />
  <Execution ProcessID="0" ThreadID="0" />
  <Channel>DNS Server</Channel>
  <Computer>S0213DC01.aiscorp.local</Computer>
  <Security />
  </System>
- <EventData Name="DNS_EVENT_DS_INTERFACE_ERROR">
  <Data Name="param1" />
  <Binary>51000000</Binary>
  </EventData>
  </Event>

Last night the error popped up again at 8:06:08PM.  Same messages as above.

Can anyone advise? This is driving me nuts although AD seems to be working fine.