Hyper-v VM going to saved state

I have a server 2008 r2 system with Hyper-V running a windows server 2008 standard VM.  The VM was converted from a physical system.  The system has been running without issue until this week.  The VM is now dropping to "Save" state and then starting back up.  This is causing a great deal of frustration for my client.  I have added the Hyper-V folders to the antivirus exclusion list.