Could Flight 370's black boxes have 'pinger' problems?

Time is running out to find the locator 'pings' from Flight 370's black boxes. They are supposed to continually transmit for 30 days. So far there is no sign of them. CNN safety analyst David Soucie has new reporting on the possibility that they are losing power faster than expected. Anderson spoke with him and David Gallo, who co-led the search for Air France Flight 447.