My customer has a Partner ACS R7, No caller ID on lines 3 and 4, just started a few days ago on two of their 4 lines. I moved/swapped the line to different ports, the numbers that had displayed caller ID still did an the ones that didn't still didn't. First guess Provider has stopped sending Caller ID. I conneced a Caller ID single line phone to the line cords that plugs into the Partner, ALL lines displayed caller ID. When I was done testing 3 of the 4 lines now have no caller ID and one still does. Second test , my spare ACS R7 power up default plug the lines into it, phone connected to ext. 10. same three lines no caller ID one does. Move one of the lines that does not display caller ID to all 5 ports, no caller ID. Move the line that does display caller ID to different ports always displayed caller ID. Removed bridge clips on 66 block to isolate line that does not show caller ID, Punched new cord down on Provider side of 66 block, plugged into system, no caller ID. Provider says everything is good on their end. Any Ideas