I have a customer with a 8 x 24 DS. I installed a PA2A several weeks ago for paging and loud bell ringing. I punched it on the Violet Red pair on the CO Line side. It works great but I have a phantom ringing problem. Every once in a while it will ring for about a minute and then stop on it own. I looked at programming and do not see anything wrong. Any suggestions to stop the phantom ringing would be appreciated.