Hello,
Adding to other replies... Have you run and rolled Standard Cost via the Standard Cost Worksheet? This allows you to take component costs, Work Center capacity costs and then rill them up to the manufactured Item to create the new or updated Standard Cost. You can roll a single Item off the Item Card under Related/Bill of Materials/Production/Calc. Production Std. Cost.
I would run the Standard Cost Worksheet as this will cover all your items as it sounds like others might not reflect the Standard Cost. One last note, I am guessing that your Manufactured Item has a Routing to reflect capacity time.
Thanks,
Steve