Ships carrying sophisticated deep-sea sound equipment are heading to an area where a Chinese vessel searching for the missing Malaysian plane has twice detected a pulse signal. An Australian naval vessel is first investigating a possible third signal elsewhere in the massive search zone. None have been confirmed as coming from the flight recorders of MH370. Meanwhile families of the missing passengers have attended a prayer service in Kuala Lumpur. The plane disappeared four weeks ago with 239 people on board. Investigators believe it crashed in the Indian Ocean although no confirmed debris has been found. Australian co-ordinators said on Sunday that new analysis of satellite data meant…