Input errors match ignored on sh interface

[kmcginniss]

    I have 7206vxr router with three gigabit interfaces. A couple of times a day I get a SNMP message the router has gone down and come right back up. A "show interface" on all three gigabit interfaces shows input errors and ignored match exactly. All hardware has been replaced. It's not a case of traffic overload because it happens in the middle of the night when traffic is light. Any suggestions?

Thanks.