It sounds like the line assignments were copied over, which means there's probably outside lines programmed onto your new sets, which may not be what you want.
Do a Feature #0 and press the buttons on the phone, and it will tell you what they were programmed to. If you've copied the button programming and didn't mean to it will have to be reprogrammed.
If you just want to silence them, go into the config (Feature **266344), look up the set you want to change, and go to Line Access->Line Assignment. Here you'll have to look up the outside lines and change them from Ring or Appear&Ring to Appear Only perhaps (depending on your configuration.)