Wierd one! Night 1 rings to cordless phone 405. 405 is a button on 3 super sets. When a call comes in it rings 405 and gets answered on 405 but continues to ring the 405 buttons of the 3 super sets. When you pickup on the super set button it stops ringing and says hangup. Going off hook on the cordless lights the super set buttons. Why would it keep ringing the super sets after 405 is answered??