>> good wednesday morning, everybody. we will get right to it. more cautious optimism this morning in the search for malaysia airlines flight 370. >> underwater signals believed to be from the black boxes have been relocated again. they were first picked up over the weekend, but then lost. >> lana zak with details. good morning, lana. >> reporter: good morning. john and diana. a month after the jumbo jet's mysterious disappearance, this may be the first real find that answers could be forthcoming. after all those hours and days, crews have spent searching and listening for the sound of pings, at last it seems there are some encouraging developments. ocean shield has now detected four transmissions in the same broad area. >> reporter: but the race is on to connect those sounds with the missing malaysian plane's black boxes before those rapidly fading batteries die out completely.