Active Directory Authentication fails at random times

Issue

• AD authentication will sometimes not work, and when we restart samba, nmb and winbind, it works again.
• All of the services are running and have not crashed.
• There is also no log file that we can find that something has happened to the services.
• This happens periodically and it seems to be at random times, however we do not use this box very often.
• There is no difference that we can see between the files of the box that is working fine and this box.