**If** this indeed occurred, it seems to me to be pretty important in working out causation as it would show:
- there was something wrong enough to cause incoherence and, it seems likely, no further subsequent contact;
- radio working, with Fariq speaking; but
- crucially: there is no attempt by MH 370 to hide itself (e.g. by simply not answering) and indeed there is action inconsistent with an attempt at stealth
The latter would be hard to reconcile with a rogue flight deck or intruder bent on stealth, unless it is the aftermath of a scenario similar to FedEx 705 with either: a rogue left able to fly stealthily and who does so, or no-one left able to continue flying.
911 hijackers mistakenly transmitted to ATC when they meant to make an announcement to the cabin, the reported mumbling could simply be a mis-keyed mic from a rouge on the flight deck.
Mickjoebill