Make a journal entry and write off the checks in the current period.  Debit the checking account for the net check total and credit the wage expense or whatever you prefer, then clear both checks and the journal entry in the bank rec.  If you void the checks it will affect the 941 and taxes but technically this wouldn't be a void.  Most states require the checks to be impounded but I know many clients write off the uncleared checks after a year.