Customer was experiencing calls being disconnected when they put the calls from lines 1 & 2 on hold and go to page. We have literally exhausted all troubleshooting avenues including replacing the phone system. This issue continues to happen. We have replaced wiring from demarc to KSU, replaced phones, metered the CO lines and it still continues. We have engaged the phone company in the past with no success. We are engaging them again. Has anyone had this issue or have any suggestions?