Skynews reporting that sources at Inmarsat have confirmed that data packet audio pings were being received for 5 hours after aircraft radar contact lost.
No mention of 'audio' in the actual Inmarsat media release:
Inmarsat statement on Malaysia Airlines flight MH370
14 March 2014: Inmarsat has issued the following statement regarding Malaysia Airlines flight MH370.
Routine, automated signals were registered on the Inmarsat network from Malaysia Airlines flight MH370 during its flight from Kuala Lumpur.
This information was provided to our partner SITA, which in turn has shared it with Malaysia Airlines.
For further information, please contact Malaysia Airlines.
Inmarsat statement on Malaysia Airlines flight MH370 - Inmarsat