threemiles - My apologies for my misreading of the frequencies.
However, there's a good discussion in the link below that raises the possibility of a dying ULB producing a variance in frequency that could make its signal hard to distinguish from marine mammal noises.
http://mashable.com/2014/04/07/malay...-pings-whales/
Last edited by onetrack; 28th Apr 2014 at 08:29.
Reason: addendum ..