Hi, I am struggling with a problem where calls are being created on ZAP channel, but no call exists. I have 2 X100P cards 1st = BT, 2nd Telewest, with no problems on BT line. I have carried out various test on signalling types, Kewlstart, Loopstart, Groundstart and E&M. Only Kewlstart and Loopstart appear to work, but Kewlstart generates incoming calls every 20 - 30 sec, where as Loopstart can run for upto 5 min without an auto generated incoming call. BT line if running Kewlstart ok. Have tried both cards to ensure it is not hardware issue. Checked physical wiring, which all seems good. Can anyone suggest further changes/tests? Thanks in advance. Robert Brown I can post zaptel and zapata files if that will help.