Is that one of the brand new treadles from Singer? If so...while they don't have a great reputation, it's likely that it just needs some lubrication. Look in your manual for oiling points for the machine itself and then follow the metal pieces down to the foot pedal. Oil every place where there is a joint with metal on metal. Use only sewing machine oil or Tri-Flow (do not use 3-in-1 oil or WD40). See if that quiets it down.
After you first oil the pedal, you might want to put a rubber mat or something under it to catch any drips so that you don't oil your floor.
Good luck.
John